If you're asking this totally out of nowhere, I'm gna say MAC technakohl, since that's the only eyeliner I know that (1) doesn't seem to smear at all, (2) is super easy to apply, (3) hasn't given an allergic reaction to any of my girlfriends, even the ones who are allergic to ALL THE THINGS.
Stila All-day Waterproof liquid eye-liner. It's just short of $30 CAD so a bit pricy but it's worth every penny. Even if you're been using it a couple of times a week for over a year so it's running low, the colour payoff stays pretty near fully opaque. It'll stay on through the sloppiest nights out clubbing, regardless of any sweat and such. The applicator is great, as well. Perfect for just liner on the top or a cat-eye with a pretty fine felt-tip.
Heya! depends on what quality you want. If you want a name brand i would say go To M. A. C or Sephora or if ya just want A drugstore brand I'd say Rimmel or Revlon. Those are the ones I use because it's intense in color.