I know I've bought some weird stuff just because it's cool... even though I have no practical use for it... such as:
1) PASGT kevlar helmet (military surplus)
2) A smoke bomb that generates 40,000 cubic feet of smoke (nearly an entire football field covered by 1 foot of smoke)
3) 20 rolls of raffle tickets with 500 pairs of tickets on each roll (20,000 total tickets)
I know I'm not the only one to buy random stuff just because it seemed cool at the time. What have you bought?