Heavily padded pushup bra. They're available in strapless too. I personally like the "modular strap" kind that you can wear with or without straps, and change the look of the straps depending on what you wear. I got mine at Sears.
FanExpo - fem!Iron Man Mark VII (99% complete - The Iron Man Armor Project
), Steampunk something (90% complete)
Atomic Lollipop - raver!Sailor Mars; Non-Novice Craftsmanship Award for Steampunk Airship Pirate
Polaris - Starfleet command officer
Anime North - Lacus Clyne, Steampunk Airship Pirate, raver!Sailor Mars
Steampunk World's Fair (NJ) - Airship Pirate
STEAM: Pushing for education focused on Science, Technology, Engineering, Art, and Math