What backup software do you recommend? I just want to keep my external hard drive in sync, but at the moment I have to do that manually. (I'm using Windows, and I'm trying to avoid having to use cygwin, so rsync is not really an option)
robocopy.exe /MIR <source> <target>
Create a scheduled task, set your external drive as the target, and forget. robocopy.exe is a built-in utility for Windows 7 and can be freely downloaded for via the resource pack. Also consider an offsite solution such as Windows Live Mesh for the free 5GB to create offsite backups of the most important folders. Never know when a catastrophic event (theft, fire) can take out your backups.
Ditto if you screw up - you have to catch it before the next backup otherwise you're boned.
Alternatively, for syncing and not real backuping (no timestamped snapshots, for example), I've used FreeFileSync[1] successfully in the past.
Throw TrueCrypt into the mix, and you've got a pretty good and secure backup.
Arq is a good backup-to-cloud service if you're conscious of where your data goes(S3) and who has the keys(Only you).
They're both indie programmers out of Boston too, which may be some of my bias, but check'm out!
Backup to me (and most others that I've talked to) means "I can restore all my data, my entire hard drive, and be back to where I was yesterday, so if I screw up my kernel tonight, I can just use the backup to revert to my pre-kernel hacking spree".
(to an average joe, it means the same thing, but not as much detail)