I'm in an corporate I.T. network worldwide monitor support position, and work 12 hour nights, 6pm-6am. 48 hours one week, (Monday, Tuesday, Saturday, Sunday) and then 36 hours the next week (Wednesday, Thursday, Friday). 8 hours of the 48 hour week is guaranteed overtime, AND, I get a hourly shift bonus for working nights.
There's 4 people covering 24/7/365, and with the other two working the opposite days shift (they are on the 36 hour week that I'm on the 48 hour week).
It can be quite stressful at times, but I basically just have to stay awake, can play on the internet to do so, and only have to respond to network issues as they (IF they) come up. I then call out the local support to handle it.
I was a regular field tech, and had spinal surgery (neck, discectomy and fusion at 3 levels) back in mid 2007. After coming back to work still wearing a hard-collar, they quickly found out I couldn't continue to easily do field work. So, I fell into this job early 2008, and have been doing it ever since.