I was in Snooper's Paradise one day, around a year or so ago, and I found this absolutely wonderfully looking record by Pierre Henry:
It is from the "Philips' Prospective 21e Siècle" series, which was started in the sixties to promote experimental music. Every record in the series is housed in a different, stunningly beautiful silver foil sleeve, and I cannot tell you how much I want the entire collection. Taken as a whole, maybe the best example of record sleeve design ever?
I can't vouch for any of the other records personally, though there are some heavy names in there, but the music on "Le Voyage", which is conceptually based upon the Tibetan Book of The Dead, is incredible. Pierre Henry explored the very sound of sound, and you just don't hear sound like this now. It is physical, malleable, it sounds like it is literally burrowing in to your head. It's disturbing.
Ogle over more pictures and hear more about these so called "Silver Records" here:
Incidentally, Woebot's is a particularly great music blog, full of frequently hilarious musings. Here's a link to a two part guide to Indian music and its legacy that I found there: