I have cooling fans for both my IDE and SCSI drives. In the lab, we have cooling fans on the drives at all times. Optimize your hard drive on a daily basis. As much of a pain in the butt as this may be for some, optimizing your drive has several benefits. Besides optimizing the files, this process also catches many minor problems that may manifest themselves as a major problem later.
Examples are cross-linked files, or orphans.
Another good reason is if you do have a problem accessing data on your drive when a utility is run, such as Norton, Nuts and Bolts, Tiramisu, etc., the chances of recovery are much higher if the drive has been optimized recently. I would also recommend running Spinrite on all of your drives once a quarter at level 5. TIP IT is also and excellent tool for Zip disks. I want to mention that it is not too difficult to tax a power supply in some systems if they are fully loaded. If possible, I would recommend making sure that the systems have a decent power supply.