(heck, the draft editing gives error messages )
Jak II - I have nothing especially nice thing to name, but several (just to name some): freedom, glitches (how's that good? only one of those bug hinders gameplay and offers no fun, but the rest does), marks of being well-made.
Super smash bros (all of them) - (free, pure, well made) fun. 'nuff said.
Rayman (first) - just classic - old, yet good. nostalgia also in the pack.
Rayman (the second, PS2 version) - offers a large world, but it's not the good thing. the good thing is the game itself, playing it through. too bad it's not that fun in between the playthrus.
Rayman 3 - read previous, just more extremely fun playthru times, not that long lasting extras, and nostalgia (i played this when i was seven. liked every minute). bit too new feeling drops this behind the previous 2.
Jak 3 - read Jak II. the reason this is not the second is that it lacks the actuality of the first game (more weapons, the desert, and spargus city are not a bad things, but haven city and the surroundings and characters were raped well). good game nonetheless.
Sly Raccoon (and the thievius raccoonus) - this just is so fun little platformer which actually needs some brain - this is not straightforward like ratchets or even jaks, because you're so vulnerable.
Jak and daxter - read previous jaks. offers no weapons, but you wouldn't need em anyway. puzzling and fun.
Ratchet and clank (first) - offers large worlds and fun bugs. thing is, the gameplay is pretty simple - shoot, whack, spray, and pray. much more actual than the 2 and 3 tho.
Ratchet Deadlocked/gladiator - modern feeling, but this one is much darker, arena like, and offers a lot of customization possibilities, fun co-op, and (only few) bugs.
Please note:
Downloadable/browser/minecraft/terraria games are NOT listed due to the thread title. noteworthy ones:
LF2 - Duh...
HF - read ^
Soldat - read ^^
minecraft - ...
terraria - read ^