If it's a proper and well though-out rant it can be quite interesting... But if it's just someone sitting there bashing on something for hardly any other reason than for example "But *random person* said that thing sucks, then I have to think it sucks too" or something similar...
As for myself, I tend to rant alot, but that's because I'm a very sad and depressing person >->
Why am I freezing even tho I'm almost fully dressed and under 3 blankets? x-x