The Reveal Bra that cybernova linked is actually really great. You can get a lot of lift out of a "bra" like that as long as you stick it to yourself right! You apply the bottom of the adhesive to the... underside... first, then lift/position them to get the shape you want before you apply the rest of the adhesive. It can put a little stress on your skin if you're trying to pull them up a lot but it looks great!
Vengeful Gladiator's Battlegear (World of Warcraft) - Blizzcon '13
Lara Croft (Tomb Raider) - Launch Party March '13