I've written about this many times before, so I'm sure everybody is getting tired of me harping on it. But people who drive slow in the left lanes of freeways (especially rural freeways) are a huge pet peeve of mine. It would be great if there were actually signs like the following on America's highways:
This (obviously photoshopped) picture is several years old, but it gets the point across: the left lane is for passing only. Traffic moves safer and more efficiently when slower vehicles stay out of the left lane. If you can't figure it out, then get off the damn highway.
My hope for 2013 is for more motorists to understand and observe this simple concept, and for more state highway patrols to ticket the ones who don't.
Everybody have a safe and happy 2013!