The first “official” space item I had to have when I was interning at Johnson Space Center was a space pen. I bought the one above in 1999, and still use it on occasion, since it’s so darn compact. (I think I need a new cartridge though.) It does indeed write at any angle, underwater, etc etc etc. I picked out a few other neat ones I saw from the website, for your perusal and possible Christmas shopping inspiration:

It’s rainbow and awfully cool!

Neat grid pattern/texture on this one.

Unfortunately, there’s no way to really tell what the commemorative moon landing engraving looks like. But it’s probably cool.