Double EXP Weekend

Double EXP Weekend is a Halo 3 Playlist that features

GrifBall

Rockets

Living Dead

Team Snipers

Legendary Brawl

And Sometimes holiday playlists

Double EXP Weekends tends to feature a lot of the playlist that are different and that bungie doesnt want add permanently. In Double EXP Weekend when you win a game you get two EXP instead of just one.