World of Warcraft is a paid game. Its practically shareware. U can try it for a few days. Believed it was 1 month. Don't blame me if I am wrong. After that you will have to pay to play that game
On my website you find a lot of full free action-games. Open source to be specific.
I searched for you... Cube 2: sauerbraten, warsow, urban terror, soldat and a few more!