You know, I've thought about tattoos several times over the years, but I've never pulled the trigger. Every time I think of something I think would be good, I get tired of it eventually, and end up thinking "Glad I didn't have that inked permanently onto my body." When I was a kid, guys were getting football numbers tattooed on themselves, high school mascots, college mascots . . . . here I am, ten years out of high school, and I can't imagine what possible use a tattoo of a big paw print with a "72" in it could be to me. I mean, I've managed to remember which schools I played for, and I even remember my number (it was carefully chosen--the same number as William "Refrigerator" Perry.) I don't have a lot of use for that information anymore, but it's there if I need it, and having it tattooed on my bicep with some awesome barbed wire wouldn't make much difference at this point.
Just about the only idea that has lasted has been to get "TANSTAAFL" marked somewhere. There's a concept I don't think is going anywhere. Similarly, the research scientists who sent in pictures of their cool science tattoos to Carl Zimmer at The Loom are probably not worried that the Periodic Table or a strand of DNA or velociraptors are going to look stupid in ten years. The guy with F=MA on one arm and E=MC^2 on the other is pretty safe, too. I can see how those mean something--that's their work, not someone else's idea of cool. It's what they've chosen in their lives. I guess I could have Bloom's Taxonomy tattooed on my chest, but it doesn't seem worth it.
At the other end of the spectrum are my in-laws. If you've ever wondered if you ought to get your tattoo changed because your favorite NASCAR driver has a different number now, you MIGHT be a redneck.
(But you know I love ya, Tom!)