I'm to the point where I'm tryin to wein off. At first, like a dumbass I tried to stop from 4 mgs per day for 2 years cold turkey and experienced withdrawals. I had some shakes, random muscle spasms and I was a total bastard to anyone for a good 2 weeks lol... Its crazy shit...
I've never been dependent on other things... but addictions.
Diablo II (old school lol)
star craft - LOTR maps (again..old school)
WOW - at a few particuarly disturbing points in my life - 18 hours a day. I didn't even notice the time pass by while I played (and I still can't believe I wasn't the worst... I've spoken to some online which play the whole 24 hour day)
Oh and chocolate... can't eat enough of it but I'm trying to stop.