I very reluctantly weaned myself off it for each of my pregnancies, which for this and countless other reasons seemed to last eons. About once each year I gradually change my caffinated/decaffinated ratio so that I'm 'off the stuff' just to see that I can. I hate the idea that I'm held captive to a substance and so I do my little experiment every now and then to prove my supposed dominance over coffee.
It's one of those things that brings me a disproportionate amount of pleasure. What's yours?