Adorama has a great bundle for two-flash wireless setups: two of the Speedlite 600EX-RT and a Speedlite Transmitter ST-E3-RT for $1019.96.
Do the math: The Speedlite 600EX-RT goes for $499.00 and the Speedlite Transmitter ST-E3-RT goes for $280.99. That makes your savings $259 over buying these separately — kind of like a free ST-E3-RT, making this a hot deal. Free shipping and 2% rewards.
This is also $60 less than the same bundle deal from December 2013.
Adorama is back-ordered (on the ST-E3-RT) but accepting orders at this price.