In the photo above from SeattleCosmicGameNight20030118, Meredith_Hale? has just beaten her sister Melinda Hautala at a Raj? trick and is being flipped the Belgium Finger in return.
Let me explain the Belgium Finger. Flipping someone your middle finger, as most people in our culture know, represents the statement "Fuck you!". Since many people feel that "fuck" (as opposed to "kill" or "torture" or "maim") is the worst word in the world, this is usually taken as a pretty grave insult. However, according to Douglas Adams, at least in the American edition of his works, there is a far worse word by Galactic standards: "Belgium". Marty_Hale-Evans? and I have discovered that the finger after your middle finger (your "ring finger"--the one in between your middle finger and your little finger) is used throughout the Galaxy as the Belgium Finger. So beware: the next time someone flips you the Belgium Finger at game night, they are insulting you in the most serious (?) way imaginable.
See also bowb and swear words from science fiction.
--Ron_Hale-Evans?