Teeworlds is a free online multiplayer game, available for all major operating systems. Battle with up to 16 players in a variety of game modes, including Team Deathmatch and Capture The Flag. You can even design your own maps!
This is a fun, amazing and hilarious game. It makes me smile and laugh at some of the amzing trick shots and maneuvers people pull off. Its not a 100% perfect game but its really well executed and made. I like games that I can start quickly and easily play for 10 mins if I want then stop. I prefer games that don't have to require a time investment to play. You can't go wrong with this. Having regular updates and being so easy to larn and play gives it a A+ in my book. Highly recommended and it even more fun with friends while chatting over VoIP. Give it a shot!