I use the left lane for passing only. Most of the time I'm going faster in the right lanes- because of a slow driver in the left lane.

I used to get so pissed off cause people don't know how to use the left lane so to avoid any road rage or losing my temper I just stick to using the right lanes. Unless there's really a lot of traffic and I'm in a rush then I'll stick to the left lane.
Gotta love Houston drivers!