Chris Christie is the latest to take the ALS Ice Bucket Challenge: The NJ governor posted a video on Facebook yesterday of his two youngest kids, Bridget and Patrick, gleefully soaking him to raise awareness for Lou Gehrig's disease. If you've been on social media at all over the last few days, you've likely seen at least one of your friends take the challenge, sponsored by the nonprofit ALS Association. The rules are simple: Pour a bucket of ice water over your head, then challenge three friends to do the same within 24 hours or donate $100 to the association. The organization says it has already received $4 million in challenge donations since July 29. Christie's nominations for the next set of soakees were also big names: NJ Sen. Cory Booker, Jimmy Fallon, and Mark Zuckerberg.