Got one for you.

[meowse]

The bartender says, "We don't serve tachyons in here."
A tachyon walks into a bar.

Update: Looks like I'm (predictably) not the first person to think of it, though: several other versions appear here

Comments

[icebluenothing]

Ha! Nice.

[abostick59]

You did think of it first; it's just that tachyon jokes travel *real fast*.