I have a pair of these noisy beasts on my desk.
http://www.lacie.com/products/product.htm?pid=10491 I use Retrospect to run every night at 2:00AM and perform one of the 3 different backup options. Duplicate C Drive, Duplicate D Drive or Duplicate my content directory. I think I'm going to need more just for my content soon and I'm thinking about having an off-site backup as well.
For now this is a cheap and reliable backup that I can access fast if needed. I use Lacie drives becasue they're 3 times faster then the my older Maxtors and often the Maxtors wouldn't finish in 8 hours. The Lacie's are fast but they are a bit noisy.
I'm thinking about getting somethign for off-site just in case my office gets hit by a meteor or soemthing.