i have and it is fun
4 player chess?

seems like it would not be sound in that you may not control your own destiny. If you make all the right moves, you could still lose due to a bad move by the weakest link playing, allowing another to build a position better or faster. perhaps with opposate sides co-operating like bridge or spades?!
I'm wondering if anyone has played with a 4 person chess set, and if so, was it fun/interesting/boring etc.