My workplace does a pretty cool thing, every Monday is a "Blue Monday" whereby if you give 2 or 3 bucks to the charity of the week (sometimes the month) you can wear jeans on Monday instead of business casual. It's kinda bogus that they make us wear business casual anyway IMHO (my computer doesn't care how I dress), but whatever, if it gets people to pry open those rusty purse hinges I'll deal with it. I give religiously every Monday even tho I'm not religious.
I agree about the waste from charitble orgs tho, there has to be some overhead just to get things done of course, but it does seem that many orgs keep more than they should and it often seems that religious orgs are the top of that list. The TV preachers here in the US are the worst, I've read about $30K marble toilets in office buildings and such, sheesh, what a racket...