This definitely applies to computers- I routinely back up my data once a month. OK, maybe it's more like once every six to eight weeks, but the point is I make sure to take care of it. Losing data hurts. I once lost a very important and lengthy research paper due to a hard drive error. I don't blame the hard drive- I blame myself because I failed to act.
Anyway, you want to be sure to use an alternative browser for security (ie; not IE). Don't pay for a security suite either: AVG Free Edition is fully featured and effective as is Microsoft Security Essentials. Also download a good registry cleaner and defrag your hdd! Simple maintenance like this makes for a faster, more efficient computer.
And don't forget to reformat your hdd every six to twelve months, depending on usage.