I think this would be useful for anybody wanting to get in the currency exchange business. If I missed any feel free to post or PM me to add some more.
PP=Paypal
BTC=Bitcoin
LTC=Litecoin
AGC=Amazon Gift Card
WU=Western Union
MG=MoneyGram
WMZ=WebMoney
Google(GW)=Google Wallet
PSC=Paysafecard
BT=Bank transfer, also can be called Wire transfer
MB=Moneybookers or Skrill
Interac-E transfer=Bank transfer specific for Canadians
COD=Cash on Delivery
PZ=Payza
EMT=Email Money Transfer
CC=Credit Card
PM=PerfectMoney
EGO=EgoPay
NT=Neteller
STP=Solid Trust Pay
Other payment methods:
XOOM
OKPay
Paxum
Ukash