In Building the Perfect PC, 2nd Edition, authors Robert Bruce Thompson and Barbara Fritchman Thompson suggest a way to tell which drive is which in a RAID array: use a felt-tip marker to label each end of the cable (no stripes for drive 0, one stripe for drive 1, and so forth).
Brady was perusing one of the Ignite speaker Leo Parker Dirac’s blog, and came across a different approach:
If you’re building a RAID array for your home, or somewhere else that isn’t super-industrial-strength enterprise, here’s a tip. Get each hard drive as a different brand. That way it’s way easier to tell them apart.
For more details, including another good reason to do this, read Leo’s full entry here.