Treasure Island features one of the best free shows in Vegas--Sirens of TI. The pirate show in front of their casino has two life-sized ships in real water. It's a classic pirate fight with (fake, obviously) cannons going off and "hitting" the other ship. Of course like most shows in Vegas, there are provactive dancers dancing on the ship while the pirates are battling. The ships were even created to be able to sink once hit with the cannon (and be brought up after the show, of course).