Legend of Kyrandia, an adventure by Westwood I've played extensively in my early childhood. No, seeing the protagonist die horrible deaths every 5 meters did not my affect my 5 year old mind at all

Day of the Tentacle. Another game I've played in my early childhood. I'll keep it brief: I loved this one to death. Best game EVAR, and you should kill yourself if you disagree (or play it an be converted)
Homeworld 2. Bloody hell, this was difficult, but I have yet to find a game that makes commanding an armada of spaceships more realistic (by sci-fi standards anyway). Plus it reminds me of Ender's Game, another plus.
Master of Orion 3. I'm playing it right now, and while it is by no means as fun as the first two, it is pretty damn good. Well, bugs and stupid AI aside, of course.
Freelancer. Space-fucking-sims. When will you once again grace us with your most marvelous environments?
Diablo. I know most know the sequel, but the first one is actually pretty good, even if the character's movement speed is only slightly faster than a crawl.
Warcraft 3 + TFT. With WoW, quite a few people have forgotten this masterpiece. Lamentable, just lamentable...
Also, much thanks to whoever put up the Croc pic. You've made my day!