I find it maddening that a 'cup' is 6oz -not 8- when referencing coffee machines. To be clear, I drink 54 oz (1.6 liters) most days before lunch. Black, very black. No sweetener. JUST coffee. How people can mess up coffee with all that crap they put in there is beyond me.
I literally ache for more coffee when I start coming off my high. The cravings are mild enough to be ignored --but they're still cravings. Luckily, as addictions go, it's a cheap one.
Like Rumbas, I picked up the habit at work. There was an endless supply of free coffee and a secretary who refilled my cup every time I finished it off.