I do it once or twice a month. I have the reminder set to kick in after a week, but I tend to ignore that and just close it along with the other important notifications that come on when I boot my main desktop. (Which reminds me, I really should look into what is up with that reactor control warning. I assume one of the other guys on the project is actually dealing with it.)
Generally will remember to do it just before dealing with shots after a big game or something, but for the most part it isn't super critical. Most of my work is still currently viewed on random computer screens, so calibration is kind of moot. Mostly I've been trying to get into the habit of it, and hopefully will do some larger prints this fall.
Canon EOS 7D | EF 28 f/1.8 | EF 85 f/1.8 | EF 70-200 f/4L | EF-S 17-55 | Sigma 150-500
Flickr: Real-Luckless