Homeworld 2 demo:
http://download.cnet.com/Homeworld-2/3000-7562_4-10224086.html
Homeworld 1 demo:
http://www.softwarepod.com/10126-Homeworld-download.htm
Half Life 1:
http://www.fileplanet.com/57317/50000/fileinfo/Half-Life-1.1.1.0-Client-(Full-Client)
Minecraft
http://www.minecraft.net/download.jsp