Never official ones but sometimes players hold their own contests. Last year I remember there was like a 4th of July stunt plane show thing where or whatever where they had a flying contest or something. Also lots of servers exist with like "build the best boat" thing or whatever. So if you look around you probably should find soemthing.
The only official one I know was when Badspot had a Blockland YTMND contest and gave away a blockland key or something like that to whoever won.
