Arms
My brother and I, socking each other's arms till we were both crying.

007
We'd get into a circle and someone (James Bond) would say "0" and point to a player, then again "0" and point to another player, and when Bond would say "7, bang" and pretend to shoot a random player. People on either side of that target had to raise their hands as soon as Bond said "7". Good times.

Ground is Molten Lava
We'd throw pillows on the ground and jump on them haphazardly, pretending the ground was molten lava. We had to do the melty lava dance if we touched the ground.