One of my favourite websites ever is
http://www.despair.com/
They have some great signs, such as:
Just because you've always done it that way, doesn't mean it's not incredibly stupid.
It could be that the purpose of your life is to serve as a warning to others.
The secret to success is knowing who to blame for your failures.
Let's agree to respect each others views, no matter how wrong yours may be.
Consulting: If you're not a part of the solution, there's good money to be made in prolonging the problem.
Hard work often pays off after time, but laziness always pays off now.
Quitters never win, winners never quit, but those who never win AND never quit are idiots.
And my all time favourite:
It's always darkest just before it goes pitch black.