I don't have this problem with the rest of my fingers. Even my toenails, despite spending all day in sandals, remain respectable. But my thumbnails, regardless of what I've spent the day doing, collect a solid layer of dirt.

Back when my mother used to work for the government, she brought home a few boxes of these red mechanical pencils. Government surplus, I suppose. The only reason I bring this up, of course, is that they were, without equal, the best implement for cleaning beneath my thumbnails.

The little metal tip of the pencil was the perfect length and diameter for squeezing beneath nail and fingertip. Holding the pencil body, it was virtually effortless to scrape any dirt that had collected under my nails. The hollow tip would actually grab on to excess particles and drag them out. When you were finished, and your nail was clean, it was a simple matter to click the pencil a few times and the lead would push out a small plug of grime.

For years I used to keep one of those pencils handy just for scraping beneath my fingernails. I've never been much of a fan of mechanical pencils for actually writing, but those pencils had a real purpose, one better than simple writing.

It's been a while since I last held one of those wonderful red pencils, and I've tried to find another useful scraper for my nails. For a while I used the pointed file on my nail cutters, but it was never as stable and quick as the old pencil. An extended paper clip can also serve scraping duty in an emergency, but they too are slightly awkward to use.

Without those old pencils handily lying around the house, my thumbnails are always dirty. Perhaps one day I'll again find a suitable nail scraper, but for now, give me a few hours alone with my thumbs, and dirt will collect beneath them.