I don't want to take the time to upload this OS, and have no way to back it up should things go wrong. Having a DVD I can pop in and a few minutes later, I'm go

I don't want to take the time to upload this OS, and have no way to back it up should things go wrong. Having a DVD I can pop in and a few minutes later, I'm good to go. Reloading the entire OS does not seem fun. What would be ideal would be if I could get Lion on a USB drive like you can with a MacBook Air. Or even better, a special device with Thundebolt. I'd pay more to be able to install the binary faster than I could downloading it, or through my DVD drive. edit: I know that when you back up your hard drive, you back up your OS as well. Having said that, if my computer gets corrupted, I don't want to lose everything.