Concealer is, hands down, my favorite beauty product. (And for those of you who know about my eyelash-curler obsession, that's saying a lot.) Got a zit? There's a concealer for that (try MAC Pro Longwear, shown below. Buh-bye, blemish). Dark circles? There's one for that, too: Benefit's Ooh La Lift!, which is so positively lightweight and invisible, I have a hard time calling it makeup. Just want to lighten and brighten? Yep -- you guessed it. Maybelline's Instant Age Perfector Double Face Perfector, a highlighter and concealer in one, does both. Those are my favorites; what are yours?