Princess Threea and Luke Fivewalker, in case you were wondering.

This seems to be a bigger deal every year, so i figured I couldn't ignore it and keep my geek cred.
Frankly, before maybe five years ago, I hadn't really heard the pun. Don't know where it started or when it really caught on.
It was a clue on Jeopardy! a few years ago, so that's where I'd start looking.

Also check out Lucas Numbers, Movie Night and, of course, Hamlet II: Claudius Strikes Back.