Trek 1500 road bike, Giant Trinity Alliance tri bike
I'm not sure if you're trolling or not, so I'm going to assume that you are *not* and give you a completely serious, totally straight answer.
The Giro Advantage II is the best combination aero helmet/swim cap on the market right now. The "fin" off the back of the helmet reduces drag in the water, and then on the bike gives you a substantial aerodnamic savings. It also protects your head from the jostling that always occurs during the mass open-water swim starts, so what's not to like!