A great cross and circle game for two to four players (see instructions here).
Pretty much any models can be used as game pieces, just scale them to fit on a 2 cm circular base! I used Makerbot's Aztec chief (42 % scale), Saf's Low Poly Owl Statue (can't remember the scale...), FLOWALISTIK's Low Poly Squirtle (50 % scale) and 3DHubs's King Marvin (90 % scale).
1) Make yourself a makerboard
2) print the background pieces four times in a rather subtle color
3) print the color pieces once in each of the four colors you like best
4) think of cool figurines, scale them to fit on a 2 cm circular base and print 4 of each color
5) print a die if you don't already have one and start playing!
no supports needed, prints very well in PLA with 0.3 mm layers