Added KAMI and Zigfrak.
Also, I added this to the Trivia section since it worked for a bunch of games I tried:
Q: How do you determine if a game is Launcher-free on Steam?
A: Simple: install the game and launch it once (this step is important, because this finalises the installation). Shut down Steam and temporarily move all the files in the root Steam folder somewhere else. Locate game folder, locate the .exe, run it. Either you get an error message (or it does nothing at all), or the game just runs. If it just runs, it is Launcher-free.
[WHAT I ADDED]
Q: I did that, but it still won't work.
A: Delete steam_api.dll and SteamworksNative.dll, if present, from that game's folder.
[/WHAT I ADDED] http://steam.wikia.com/wiki/List_of_DRM-free_games