They have some REALLY old games on there, too, which are real gems. I downloaded Waxworks from them, but I haven't gotten too far in it (did the Jack the Ripper level first, figured it would be the least interesting, and the police just keep finding me and sending me off to the gallows), but another old PC adventure I played once or twice, Personal Nightmare, is up. If you can get past the ancient, barely EGA graphics, that one's not bad, either.
EDIT: They do seem to gain and lose licenses a bit, though...I purchased a racing game from them that they would no longer be able to sell after a certain date, so if you bought it already you had to hang onto your download because you couldn't get it from them after the date passed. Also, I can still apparently download one game I bought, but it's no longer on the site for sale (it was a Resident Evil-type game called ObsCure, pretty fun, actually).
But, they added Psychonauts when I wasn't looking, and damn if I haven't heard good things about THAT...