TOO MUCH WORD TWIST (HIT DOCTOR SMUT WOW)

STOP. POT. POTS. TOP. TOPS. SPOT...

Explanation: Last night, as I headed out of my neighborhood, I saw the stop sign at the intersection with the main road. My mind saw it and immediately started churning out the words you can create with those letters. This would be an indication that I have been playing way too much Word Twist on Facebook. Just for the record, the following words can be created from the letters in STOP (3 letters or greater):

TOPS
STOP
SPOT
POTS
POST
OPTS
TOP
SOT
SOP
POT
OPT
OPS

Special Blog Challenge: The letters in STOP can be used to create 12 different words of 3 letters or more. Can you find a four letter word which will create more than 12 words?*

*I should note that I don't actually have an answer to this question.