dont know exactly how unknown these games are, but oh well.

PS2

the thing

zone of the enders 1&2

evergrace

Rune: viking warlord

warhammer 40,000: fire warrior

redfaction 1&2 (love it)

PS1

parasite eve 1&2

chocobo racing (squaresoft version of mario kart. awsome)

reboot (based on the show)

street sk8ter 2 (was better than tonay hawk, but was pummeled in sales)

SEGA MASTER SYSTEM (I know its not sony, but these are great games none of my friends heard of)

thunder blade

rastan

the ninja

choplifter

penguin land