sacj93: I can think of a few old games that are barely remembered, if at all:
G-NOME by 7th Level (A decent Mechwarrior 3 clone)
Hellbender by Microsoft (A sequel to an earlier game called Fury3, sort of like Descent meets Wing Commander)
X-Wing vs TIE Fighter (ok, so this IS remembered, but it was GOOD)
Star Trek Voyager: Elite Force (Great game that had a pretty mediocre sequel)
Heavy Gear (Another good Mechwarrior clone)
I knew these ones, though only played the demos at most.
. Fury3 actually used the TV engine. I don't know if Hellbender's engine was a modified version of that or something new - it was actually Direct3D-accelerated so looked much better.