BigBadBabar introduced me to My Brute, which has been a fun diversion. Check it out and make a brute to challenge mine. Basically you make a character and level it up (gaining hit points, strength and other attributes, new weapons, etc.) by fighting against other brutes.

Warnings: it is addictive, but you only get a limited number of fights each day. So you can’t waste unlimited time on it (which I think is good). But you do need to play daily (or close to) to continue progressing. Also, the servers are often shut down late (Eastern time) for maintenance, so it’s best to get your bruting done early in the day.