I've been a huge fan of colored mascaras for a long time, it's quite difficult to find really good, pigmented ones. I've been using and loving the colored Zoom Lash mascaras that MAC released early this year. I use a white primer, then coat on 2-3 layers of colored mascara, usually Blue Charge or Plum Reserve. I only wear colored mascara on my lower lashes though, for that "pop of color" effect. But sometimes I'm feeling fierce and I'll wear one color on the top and a different color on the bottom.

I used to wear brown mascara when I was a teenager, looked softer and more natural - decent makeup for being in school all day long :)