agreed on aphex twin's selected ambient II (most his stuff is good to great, with a few exceptions)
clouddead- ten
boards of canada- music has a right to the children
can- tago mago (although my friend said this was top ten music went it was released in germany- so it is not exactly alternative)
nurse with wound- spiral insana
hood- cold house- interesting version of early 90s british drone rock, electronics and hiphop
my bloody valentine- glider ep
olivia tremor control- black forest
autechre- chiastic slide
miles davis- panthalassa (while their are many good lps from miles' fusion period, this is an excellent remix by jack of all trades producer bill laswell using the best tracks of miles' fusion period)