By 1967, UDP had made serious headway into the International Times and UFO scene, playing alongside AMM, Pink Floyd, and Tomorrow. The electronic group’s influence over the Beatles became evident when both groups performed at the legendary Million Volt Light and Sound Rave at the Roundhouse in early winter. The event was a pivotal moment for electronic enthusiasts in London. In addition to a set of tape-manipulated music by UDP, the Beatles followed with their one-time only rendition of "Carnival of Light," a 15-minute sound collage of organ drones, tape loops, spoken word, and rhythmic flourishes assembled by McCartney in the studio. Though UDP would disband later in the year, the influence of Delia Derbyshire and Peter Zinovieff over their peers remains inestimable.

Availability of recordings: no known recordings exist of the Million Volt Light and Sound Rave and neither do studio versions of the Beatles’ "Carnival of Light." According to rumors circulating between collectors over the last three decades, Paul McCartney has attempted to release "Carnival" in various truncated forms on both Beatles’ and Wings’ compilations but to no avail. Unit Delta Plus, Delia Derbyshire, and Peter Zinovieff’s compositions can be heard on various BBC Radiophonic Workshop compilations as well as the much-sought-after White Noise debut Electric Storm featuring Derbyshire and David Vorhaus.

Spooky factor: strange, cosmic, and ultimately quite poppy, the experimental recordings of Derbyshire and Zinovieff did much to bridge the gap between the European avant-garde of the '40s and '50s and the rock ‘n' roll world that followed. The Radiophonic Workshop played a particularly pivotal role developing FXs and analogue synthesizer techniques that would influence countless British left-fielders from AMM, Syd Barrett, Robert Wyatt, and Brian Eno to Sonic Boom, Mixmaster Morris, and Aphex Twin.

Pink Floyd - The "Household Objects" recordings, London, c. 1973

Whatever the contemporary consensus of Pink Floyd by current garage-indie-minimal-electro-punk hipsters, very few of these snobbish prog haters know of Waters and Co.’s DIY recordings in the fall 1973, otherwise known as the "household objects" experiment. It seems the band was attempting the ultimate punk statement years before Johnny Rotten famously sported an "I HATE PINK FLOYD" T-shirt in the Sex Pistols. Conceived by Waters in the wake of forays into the post-Syd Barrett ambience of Atom Heart Mother, Obscured by Clouds, and Meddle, "Household Objects" had the band using random, detuned objects d’trouve like wineglasses, rubber bands, and pots and pans to create what would have been a most bizarre follow-up to Darkside of the Moon. However sessions ground to a halt within a few months after the monolithic “Shine on You Crazy Diamond” began to take shape and the maximalist jazz-rock opus Wish You Were Here soon followed.

Availability of recordings: uncertain. Depending on what Floydian you confront with the question, you may get a variety of slack-jawed theories and circumlocution. While most agree that the whole of the sessions was scrapped before they really got off the ground due to a lack of label interest, others claim that large portions of these premature experiments have been bootlegged and circulate among fans while other bits and bobs found their way onto Wish You Were Here.

Spooky factor: after Barrett took a permanent hiatus from Pink Floyd, everything Waters and Dave Gilmour touched had a slightly scary - and, by scary I mean, of course, pompous and obnoxious - distinction. Although kudos must given to a club band who reacted to the loss of their resident genius and guitarist by reinventing themselves as the biggest arena act in history, Floyd’s post-Syd Barrett albums after Meddle, particularly Animals, The Wall, and The Division Bell might have been slightly bearable had they turned down the prog and done some serious housecleaning of their own.

Chris Bell - I Am the Cosmos, Memphis, London, Paris, c. 1974-1977

These days making a statement like “Alex Chilton and Chris Bell were the Lennon and McCartney of their time” would meet with little dissent from true pop fans. The name “Big Star” alone stands practically unmatched in the taxonomy of brilliant-bands-that-deserved-to-make-it-big-but-never-did.

If Chilton continued to plow beyond his Anglophiliac, harmony and jangle-guitar image in #1 Record and Radio City with the darker blues and R&B work of Like Flies on Sherbet and Third/Sister Lovers, Bell’s posthumous image remains forever tied to the soaring harmonies, crystalline melodies, and studio obsessions of Big Star. Distraught with his lack of success and frustrated with his bandmates, singer-songwriter Bell exited from Big Star in 1972 and pursued his own solo recordings.

Rumors of heavy drug use and homosexuality dogged Bell constantly throughout this period, leading him to England and France where he continued recording sporadically for years before returning to Memphis. The collection of songs he returned with were some of the most melodious, blissful, and yet sorrowful examples of blue-eyed soul ever created, as touching and brilliant as anything by his former compatriot Chilton. But record companies were loathe to take on Bell and the guitarist fell into a deeper depression. Before his tragic death in an auto accident in midtown Memphis in 1978, Bell had failed to release but one solo single to little attention. Although it would take 15 years for I Am the Cosmos to get a proper release, the mystique surrounding Bell’s music influenced every dream-pop, shoegaze, and alt-country band from the 1980s and '90s.

Availability of recordings: easy. I Am the Cosmos was released on Rykodisc in 1992 and can be purchased at any indie record store or major online music seller.

Spooky factor: overdubbed harmonies and clashing, beautiful guitar chords don’t get any better than this, but Bell’s aching vocals and somber lyrics can find even the most well-adjusted listener reaching for a toaster and the bathtub faucet.

Pussy Galore - Exile on Main Street, 1986

Few bands have left a trail of sonic carnage as mutilated and indecipherable as Washington, D.C., transplants Pussy Galore.

Brought up on '60s garage punk, rockabilly, experimental noise, and just plain Cramps-style trash-rock, Jon Spencer’s group of musical anarchists took to their instruments with a deconstructive gusto that might have made the Stooges appear as virtuosos in comparison. Releasing punk-thrash-noise-sludge albums with names like Groovy Hate Fuck, Dial ‘M’ for Motherfucker, and Pussy Gold 5000, did their iconoclastic tendencies have no end?

Although the origin of their decision to record an entire album cover of Exile on Main Street is unclear - Spencer claims it came from Thurston Moore’s threat to give the "White Album" a similar treatment, while former member Neil Hagerty also takes credit for the idea - the completed product is a sometimes brilliant, sometimes pathetic but always provocative reinterpretation of the Stones laid to waste by guitar squall, feedback, inaudible vocals, and sloppy riffs.

Recorded in only two days with a small four-track recorder and no engineers, many of the songs on Exile sink quickly into muddled detritus or spin out of control into white noise. But the album still works beautifully as a whole. Much has been made of Spencer’s education in semiotics, but how much Derrida or Baudrillard figures into this record is less important than another philosopher’s maxim, “Kill Yr Idols.” Unfortunately, no label, not even SST was willing to take a chance on its educational value and Exile on Main Street remains unreleased to this day.

Availability of recordings: Difficult. Exile on Main Street continues to make the rounds as tape-only bootlegs and through digitized downloads. Although it may take a solid weekend of searching through Web sites and blog aggregates or massive record swap lists, the prize is well worth the labor. Play it loud!

Spooky factor: Julie Cafritz’s howls and curses alongside the screech of various gnarled instruments sound more akin to a Halloween sound effects recording than good ole rock ‘n' roll. Maybe amusement parks should consider piping this into the ghost rides and haunted houses.

My Bloody Valentine - Loveless sequel, 1991-????

How does sonic genius Kevin Shields follow up the most brilliant album of the last two decades?

Why, by doing nothing, of course. After nearly bankrupting Creation Records and astounding even ambient pioneer Brian Eno with the sounds coaxed from a mere guitar, My Bloody Valentine released the era-defining Loveless and promptly went into a 15-year hibernation.

Island Records reportedly sank a half million pounds into studio time, hoping beyond hope that Shields would match his previous successes. Rumors have circulated for years that MBV recorded three or four LPs worth of gold only to have each stowed away on a shelf or burned or overdubbed ad infinitum. Slowly the other members of the band dispersed, leaving Shields to twiddle in the studio for the "perfect" sound. Valentine fans everywhere patiently await the next tremolo and distortion symphony magnifique. And while word circulates about the imminent return of MBV as soon as next year, it is doubtful that Island Records is holding its collective breath.

Availability of recordings: unless you know the combination to the secret vaults beneath what was formerly Alan McGee’s brain trust on Clerkenwell Road, London, it’s unlikely you’ll ever hear a note of these discarded tracks. You might have to satisfy yourself with Shields’s minor contributions to the Lost in Translation OST or better yet seek out the most inspired of MBV’s acolytes, including UK post-rockers Seefeel (whose debut, Quique, was re-released this year as a double-CD by Robin Guthrie’s Too Pure label) and Flying Saucer Attack, Austrian composer Christian Fennesz, and Japanese artist Nobukazu Takemura. Or else build your own “glide” guitar rig and start slashing away.

Spooky factor: the closest recording technology has ever come to capturing demons and angels in mid-flight. As one Melody Maker journalist wrote of My Bloody Valentine’s unique creation, “This is what Heaven must sound like.”