Finlay has invented his own board game. I actually don't know what it's called, but he and I played this afternoon.
The rules are very complex, and seem related to Chess - you move pieces across the board in a similar way.
For a close up of the board and playing pieces:
Sadly I lost the first round to Finlay, but he did comfort me after announcing victory "well we both really won Mummy". I guess he's assuming that if I keep losing like that I won't want to play anymore.