These are more examples of opportunities for proofreading. It seems my list gets longer each time...

This is from one PowerPoint slideshow...
Its the reason...
Its' the reason...
It's the cause

(Well, if you try all combinations, you might get it right.)

This is from a Coke website...
Whats new...

This is from a sign on the drive-through at a McDonalds...
Our soda mashine is broken. We don't have soda.

This is from a spring sale flyer...
Order your Easter lilly today!