I try not to fall into too many clichès, personally, (I'm not sure why, though) but I do fall into these:
-Playing video games for large amounts of my day
-being shy and antisocial. (not necessarily a clichè, but I always feel like the "typical shy person")
-being very geeky when it comes to science, and technology. (Seems fairly common on the internet, but still not sure if a clichè)