Today's Lesson in the Ease and Fun of Creative Rearranging

Walking through the computer science building at uni, I happened upon an interesting room. Once upon a time it must have read "consulting room" but had been changed to "insulting room." Unfortunately there was nothing Monty Python-esque going on inside.
But it makes you think: How many signs are there that with a little creative rearranging, can become a source of comedy?