This is also known as to"Pull an Eric"
There are several rules regarding the Pacman.
#1) Anyone who passes out too early at a party MUST get it.
#1a) The person hosting the party is immune, unless they aren't well respected.
#2) Anyone who asks you "What's the Pacman?" MUST get it.
#3) The same person CAN be pacmanned twice, but not at the same event.
#4) Tricking someone into asking you What the Pacman is, grants you ONE free pacman immunity.
#5) ALL PACMANS MUST be videotaped, and put on Youtube.com
History: The Pacman Originated when 2 geeks named Eric and Charlie were hanging out with a very "loose" or "sexually overactive" girl. Eric somehow ended up with his pants around his ankles. Charlie turned, saw Erics testes, and screamed "OH MY GOD I CAN SEE YOUR PACMAN". It's become quite the underground sensation ever since.
he also makes an appearance in the Bloodhound Gang song titled "Mope"
PacMan: Yo yo yo yo! What it is motherfuckers!
Dude 1: Aww shit... here comes PacMan...
Dude 2: Hey PacMan. What's up?
PacMan: Me, you bitches! I'm high on crack! Wanna freebase?
Dude 1: No PacMan! Drugs are bad...
Dude 2: Nope. Can't help you man...
PacMan: Pussies...*freebases crack* Whooooaaaaaa!!!! HOLY SHIT!!
Boxing announcers and match commentators usually call him by his nickname "Pac-Man" instead of his surname "Pacquiao", since it's easier to pronounce.