If you get the E2180 CPU at newegg they have a combo adding a motherboard for $125 total with a $20 mail-in rebate on top of that. $105 for motherboard and processor is pretty good!
Newegg.com - Computer Parts, PC Components, Laptop Computers, Digital Cameras and more!
I also saw some cheap systems on eBay using that E2160. Just search "E2160" and there are a few IF you don't want to build yourself.
Maintaining certain data is an issue for me as well. I am still debating between raid 1 and 5 and like someone else said above, you should get a good external hard drive and back it up yourself every so often. That with the combination of raid 1 or raid 5 should keep your data as safe as possible.