A10s were seen occasionally at the Atterbury Air to Ground Range. Up in the tower you would see a dot in the distance and the hit counter would spin up and the dot would turn away.
Hmmm, that's a toughie. I guess I'd have to say a 12 ga. pump (probably something like the 870 or 500). Good for both hunting and combat, and it's almost concealable (short barrel, pistol grip). JMO, but the versatility of the 12 ga. is second to none.
With the appropriate barrel / shotshell configuration one can stock the table with almost any game that's edible, and in 'combat configuration', it's a ferocious weapon.