As a flip side to the Pet Peeves thread, how about things that you find really satisfying?

I'll kick off wth a couple:

When someone tries to be a smart arse skipping the queue of traffic and then nobody lets them in.

Getting through the traffic lights before they change.

When a know-it-all gets proven wrong about something.

When your petrol is just about out but you reckon you can still get to wherever you're going without filling up and you're right.