For a minimum donation of $2 per week, employees in our department are permitted to wear jeans and sneakers on Fridays. All donations are then forwarded to the United Negro College Fund.
Not only is it a great fundraising idea, it's also a money saving tip as well. You not only save on the cost of a professional attire (one less outfit per week), but it also means fewer trips to the dry cleaners.
Of course, it goes without saying that if you're meeting with a client on a Friday, you should dress up. But I've noticed that most folks avoid Friday meetings anyway.
Have a wonderful weekend.