Don't know if anyone mentioned this, but the Cave Story remastered soundtrack is really good https://dl.dropbox.com/u/22696601/Audio/OST/CaveStoryOSTRemastered.rar
There was never an official release of the soundtrack as far as I know, and the above link is the only download I could find for it. It does appear to be missing a few tracks, however. The complete(?) soundtrack is on youtube, and the sound quality seems fine to me
My second recommendation is the Shatter soundtrack https://sidhe.bandcamp.com/album/shatter-official-videogame-soundtrack
Each track does drag on and become repetitive, but it's still good listening
Finally, I'm just going to link to my (current) favourite OCRemix tracks
http://ocremix.org/remix/OCR02808 Smartball 'Rainfall' remix
http://ocremix.org/remix/OCR02925 Castlevania: Bloodlines 'Find Me' remix
http://ocremix.org/remix/OCR02828 Metroid Prime 2: Echoes 'Bogged Down' remix
http://ocremix.org/remix/OCR01372 Shatterhand 'Shattered' remix
http://ocremix.org/remix/OCR00547 Killer Instinct 'Killer Instincts Enhanced' remix
http://ocremix.org/remix/OCR02964 Gunstar Heroes 'Bullet Hell' remix
http://ocremix.org/remix/OCR00963 Double Dragon 'Enter the Guru' remix
http://ocremix.org/remix/OCR00964 Street Fighter II: The World Warrior 'Guile's Theme (R.A.H. Mix)' remix
http://ocremix.org/remix/OCR00346 Mega Man X 'Sigmatism' remix
http://ocremix.org/remix/OCR02918 Tyrian 'Data Flux' remix
http://ocremix.org/remix/OCR02945 Donkey Kong Land 'Banaqua' remix
http://ocremix.org/remix/OCR02984 Doom Troopers: Mutant Chronicles 'Skull-Head' remix
http://ocremix.org/remix/OCR01745 Double Dragon 'The Secrets of Sosetsuken' remix
http://ocremix.org/remix/OCR01082 Raiden Trad 'Thunderous Dawn' remix
http://ocremix.org/remix/OCR01784 Street Fighter II: The World Warrior 'Clamato Fever' remix
http://ocremix.org/remix/OCR01379 Unreal Tournament 'Club Showdown' remix (This one does include some voiced lines from the game, but it's minimal and doesn't impact the song too much)
http://ocremix.org/remix/OCR02219 Sonic the Hedgehog 'The Sound of Speed' remix
http://ocremix.org/remix/OCR02504 MapleStory 'Sunrise over Mardia' remix
http://ocremix.org/remix/OCR01586 Shadow of the Colossus 'Snowfall on Forbidden Lands' remix
Hope you find something you like from this post