When I was a kid/teenager, I was an avid stamp collector. Years later, postage rates are almost triple what it was, all stamps seem to be self-adhesive, and the topics on the commemoratives rarely seem that interesting.
But I've noticed some nice new geeky stamps. At the post office, I found this quartet. Von Neumann? Richard Feynman? Coooool.
And let's not forget last year's stamp of Bucky Fuller. Probably the weirdest stamp I've ever seen!
And now, the geekiest, available end-of-September: Muppet Stamps! I'm going to have to get hundreds of them!
(Note: Never buy stamps online through the mail; get them at your post office. When you buy them through the mail, they are individually packaged in cardboard and plastic. Just about the most wasteful packaging I've ever seen. Harumph.)