Yet another great app has been released by Tim Burgess: SMART Monitor! Seasoned administrators know that hard disks fail on a regular basis -- it's not a matter of if, but when. The SMART Monitor app analyzes the reliability of hard drives and predicts drive failures. Yes, you can detect a hard drive issue before it cause a system failure and potential downtime.
Tim's app is available for $10 (one-time) via Marketplace.