Any free downloadable single player games for PC?

I'm not looking for anything special.
I'm going for vacation for 2 weeks and since I'm taking my laptop I figured I should download some games to kill time.
I won't have any internet connection so it has to be single player.
I'm open to any suggestions.
My lap top can handle Minecraft and ARMA 2 at decent settings.
All answers are greatly appreciated, thank you for your time.

OpenTTD: http://www.openttd.org/en/ Based on Transport Tycoon Deluxe, an awesome transport simulation game where you develop different means of transportation.

Cave Story (platform game): http://www.cavestory.org

Erie (a horror game): http://www.desura.com/games/erie

Full Spectrum Warrior: http://news.bigdownload.com/2008/10/07/download-full-spectrum-warrior-full-free-game/ A military squad-based third person shooter and squad strategy game. Actually a really highly rated game.

Kraven Manor: http://www.kravenmanor.com Another horror/mystery game

MechCommander 2 (source code was released by MS several years ago so it's free!): http://www.shacknews.com/file/20899/mechcommander-2-free-game

Command & Conquer: Gold (one of the classic RTS games; also released for free by publisher): http://www.fileplanet.com/180464/180000/fileinfo/Command-&-Conquer-The-First-Decade---Command-and-Conquer-Gold-(Free-Game)

The Suffering (another horror game, released for free courtesy of the USAF): http://www.gamershell.com/download_33314.shtml

Psi-Ops: The Mindgate Conspiracy (released as freeware with ads in 2009): http://www.fileplanet.com/187537/180000/fileinfo/Psi-Ops:-The-Mindgate-Conspiracy-(Free-Game)/

Also check Steam's "free to play" library. I know most of those are MMO's… Or maybe they all are, I never check 'em, but you might find something there.

And just to cover my own but, a note to the admins: All games listed above have been publicly released as either completely free, or free with built-in advertisements. The links are not to hacked or cracked versions of the games, but rather the full versions which were released by the companies that owned the rights to them.

Perfect games for killing time are casual games I think. If you don't have internect connection during your vacation, I'd advise you to download several games for free and with no trials or sign ups from http://toomkygames.com/pc-games or http://myrealgames.com with http://freegamepick.com. Have a nice vacation!

P.S. Check the TOP-10 games of these sites to download for you laptop)