Urban Decay Primer Potion: Concealer/Shadow Base
OMG. If you haven't tried this stuff, you need to! It makes your eye shadow appear a little more intense but the selling point for me is that it makes your eye shadow stick and stay in place ALL DAY LONG. Eye shadows that used to crease or slide off within a few hours now will stay on for 8 or 12 when I use this stuff before. Seriously, it's amazing.