i use a combination of sugarsync (60gb plan) + multiple 1tb hard drives (one time machine and three for archiving material). why so much?
i have a lot of data that i have collected for my research, and losing it through fire, theft, or damage would be a major blow. the time and money i put into collecting it represents years of effort.
1. sugarsync holds the crucial data + stuff i am working on this minute. if everything went bad for me here, i could still get by with the stuff i have backed up online.
2. the time machine hangs out in the office and backs up things every day. i just plug it in when i arrive.
3. one archived drive is in my bag. it carries all of the stuff that won't fit on my computer's hard drive.
4. one archived drive is in my office. i copy files over from the one in my bag every few days to keep it up to date.
5. one archived drive is at home. i copy files over from the one in my bag every few days to keep it up to date.
yes, doing it this way is about 150 dollars more expensive than the time capsule. and, it certainly takes more effort. but, i think the key is to have backups in multiple physical locations. if my house burns down tomorrow (our neighbor lost everything last winter), i am ok. if my office is broken into, i am ok. if my backpack is somehow stolen off my back, i am ok. in other words, this gives me peace of mind.
in your case, if you don't have much data, at least consider a cloud service like sugarsync. i can't tell you how many students mysteriously experience computer problems the night before papers are due. i have had it happen myself! and, it is distressing beyond the ability of words to adequately convey. i don't plan on going through that experience again.