did the "Ice Bucket Challenge" for ALS yesterday, and as you'd expect, he didn't do it like anybody else.
Instead, Charlie held a big pan over his head . . . and when he flipped it over, $10,000 IN CASH rained down on him. But he wasn't just being a jerk to mock the whole thing . . . he's actually donating all of it.
He explained, quote, "Because, let's face it, ice is going to melt, but this money is going to actually help people."
Then Charlie called out his "Two and a Half Men" buddies . . . Jon Cryer, Ashton Kutcher, and the show's creator Chuck Lorre . . . challenging them to, quote, "identically do what I just did."
He added, quote, "Come on guys, it's for a great cause."