FVF - Final Value Fee
Bump - Bring Up My post (to move your thread to the top)
NPB - None Paying Buyer
NPS - None Performing Seller
BNWL - Brand new with labels
BNIB - As above but boxed
MIB - Mint in box
TOS - Terms of Service
Shill Bidding - Using a friends or fake account to try and bump up the final price of an item.
NR - No reserve price...