DGEX.com - NXT / BTC Exchange (thread)
BTER.com - Bitcoin and Crypto-currency Exchange Platform
Vircurex.com - Exchange and Trading Platform
Cryptsy.com
PeerCover.com - NXT Ripple Gateway How-to trade Nxt on Ripple
Poloniex.com - NXT / BTC / LTC / NMC / XPM Cryptocurrency Exchange (thread)
Nxt-e.com - Professional NXT Bitcoin Litecoin Exchange Market
Bittrex.com - The Next Generation Crypto-Exchange
NxtBtc.com - NXT / BTC Exchange (No Javascript Required)
UpBit.org - Crypto Exchange
CryptoKopen.eu - Buy Nxt with Skrill
BitcoiNxt.net - NXT / EUR Exchange
LiteBit.eu - NXT / EUR Exchange
QuickNXT.com - Nxt Asset Gateway (Under Development)

Who use this several trading site? Which one is the best?