The Millenium- Begin[1968]

Absolutely perfect psych-pop album. The definition of a "lost masterpiece".
This was the most expensive album Columbia records had produced to date, and you can really tell that no expense was spared.
"Prelude/To Claudia on a Thursday" might be the best way I've ever heard an album begin.
The tragedy: the album sold abysmally, and the band was never re-signed.