Scammer List:ILikeTrtls aka Candyass (In game scam)
WillClater (Realm gold scam)
GODZMULE aka Blehs, Astryx, and Perden (Trade hack)
eaeorgusei (Trade hack)
DPSAP (In game scam)
Mineslave (Offers to open dungeons for items/potions and then doesn't ~ Possible trade hack)
Klop (Trade hack)
gostautas (Only gave a fraction of the agreed price of a planewalker)
Demonate (Paypal scams)
Dargon aka Unbreakable [forum name: combat_hunter] (Offered a WC with a 2-3 def buy in. After he received payment, he did not provide the service)
GoCryHomie (Swaps items in trade screen/Deselects)
Questionable Traders:HyphyGODZ (Made multiple attempts to force questionable trades on various mules)
Bobthepig (Possible trade hack use. Be very mindful of this user)
pdiddj (Swaps items in trade screen/Deselects)
Rytrick (Attempted to pass wisdom pots off as life pots during a trade. Be careful when trading with this user)
Essence (Attempted to pass wisdom pots off as life pots during a trade. Be careful when trading with this user)
XBeatZerX (Deselects. Be mindful of this user when trading)
TheWish (Swaps items in trade screen/Deselects)
CadXL (Attempted to pass snake oil off as a Defense pot. Be careful when trading with this user)
Quote (ghostpressure @ Apr 6 2012 09:38pm)
IGN : CadXL - Tried to pass a snake oil off as a defense pot. No items lost

Updated the list.
Thanks for the report dude :3