I was a beta tester for a program called shadowuser recently that is really an interesting concept. The software lets you run your computer in a state called shadowmode which is really a virtual volume. It can prevent spyware and other malicious code, because after running in this mode, the user decides what to save and what not to save or you can setup exclusion files and folders for automatically updating changes real time, but everything else is protected and with each reboot the system is exactly like it was before. I don't know exactly how it worked, but unlike GoBack and other technologies, it didn't slow my computer down at all.
It is really a very nice product, although, probably best for the most extreme techies.
The beta program finished and the product is probably available.