First, a reality check: Did your calculator really crash, or is the contrast just turned way down? Try pressing 2ND and hold down UP for a few seconds. If that fixes it, don't worry; it's a pretty common mistake.
If that's not it, we gotta figured out what just happened. How did you get to this point?
7:Reset…It's your own damn fault, and you should probably know that by now. Once you reset, it's gone.
Try turning it on again. If it turns on and gives you the RAM cleared screen, you're done. Anything you had in RAM at the time (anything that didn't have a * next to its name in the Mem Mgmt/Del… menu) is gone, but your calculator is fine, as well as anything you had in archive at the time. If you really, really want to recover a program that you left in RAM, you can try using DrDnar's Archive Undeleter to get it back. It allows you to recover programs that you've archived at least once before, provided that you haven't garbage collected since then.
Your batteries might simply have run out without warning. This is especially a problem if you use rechargeable batteries, which don't warn you beforehand with a "Your batteries are low" message, or if you left the calculator in a program as the batteries drained. Replace the batteries and see if your calculator works. (Make sure your "new" batteries are actually new—I once spent fifteen minutes panicking at this point before I realized they were dead as well.)
If it still doesn't turn on after you put in new batteries, try draining the calculator of power completely. To do so, take out all the batteries, including the backup battery (you'll need a screwdriver), wait a few minutes, put the batteries back in, and try to turn it on. If it turns on (probably with the RAM cleared screen), your calculator's fine, and what you had in your archive should be too. Otherwise, your calculator has really crashed. Read on to step 3.
