I recently started tightlining my eyes (applying a liner right at the base of the lashes, coming up from the underside of the upper eyelid). For more about this technique, see here: http://www.xovain.com/how-to/how-to-tighline-your-eyeliner-gif-tutorial
The first time I tried it, I used a matte Urban Decay 24/7 pencil. The pencil is kind of clumsy for getting in and around the lashes. But I was sold on the technique, and the waterproof pencil stayed on with no irritation.
I thought a brush would be an easier way to work the liner into the lash line. So I purchased the Laura Mercier cake eyeliner that you activate with water. I'm having mild irritation from it. So I'm wondering what other people use to tightline their eyes. I've heard you can also use a waterproof gel eyeliner--your favorites? Ones that don't irritate near the waterline?