Lots of people are suggesting quitting. Here's a better idea:
Are you really working all of those 12 hours? I imagine not. Probably taking a lunch break, right? Eat at your desk, use your lunch break to work out. 30min a day of strenuous stuff is all you need. Here's an example:
You don't need to go to the gym; you can do it all with bodyweight exercises: pushups, pullups (get a pullup bar that sits in a doorframe without being attached to anything, like Iron Gym, so you can put it up when you're working out and then take it down), Hindu squats (google it) and crunches will get you 90% the benefit of a more thorough workout. If you want some variety, do yoga.
5min to change, 30min of circuit training (google it) with these four exercises, 5 min to change back. If there's a shower onsite, then +10min to shower, and you still have 10min left to relax and start your lunch.
FYI BackupPC is pretty nice, itself.
In 1995, my pal Robert (or was it Jeff?) downloaded a Slackware distro -- via slow modem, onto floppies. It took about a week.
We all passed the floppy set around, installing Linux onto our computers. By February of 1996, id had released the Quake demo. I had Win95 on my old craptastic Packard Bell, but it simply wouldn't run Quake. I spent hours trying to get the SVGALib Quake to run. I distinctly recall nuking my system in an effort to get X running, and somehow typing (as root) "rm -rf / usr/local/lib". See that extra space? Yeah, that was fun.
I got a new computer, but couldn't get Win95 to run, so I switched to OS2/Warp. It wouldn't boot at all. Linux would run, but would crash a lot. I finally discovered that the scumbags who sold me the computer had swapped the new 486 Intel chip for a much older and slower Cyrix chip, and overclocked the hell out of it so that it'd show the appropriate Mhz at boot.
I finally switched that POS out for a new computer, and ran dual-boot Linux and Win95 for several more years. Today I use Macs, but they're mainly pretty window dressing for terminal sessions on Linux machines.
Remember to say hello to your bank teller.