Can I throw a late entry into the contest. Actually, it doesn't even qualify since it's a Filemaker 12 database, not Excel. Regardless, I think it has to be the geekiest backpacking gear checklist ever made. I built lots of Filemaker databases for my company, and I built this one out of need, and over the years I've continually refined it. When Filemaker 12 came out, it jumped it to a new level.
If you don't have Filemaker 12, you can still run this on an iPad or iPhone by downloading the Filemaker GO app. You can download the database from my website at www.apexweb.com.