Nikon's official workaround for wirelessly getting images from the D4 is the WT-5A, a wireless transmitter that'll set you back more than $800 for functionality that seems pretty basic in the age of universal Wi-Fi. So Voudas, a reader at NikonRumors, tried a workaround, and put together a much less expensive way of getting the same functionality:
"The idea was to connect the small VAP11G portable WiFi bridge device (available on eBay and Amazon) to the D4's Ethernet port in order to use it through WiFi. I setup the Ethernet connection of the D4 and then used the VAP11G device to connect through my WiFi. I then used my laptop and iPhone to check the WiFi connectivity with the D4. It worked like a charm!
The limitation of the device is that it didn't act as an access point - it would always need an established WiFi network, but the important thing was to prove that the price of the WT-5 price is ridiculously high ($877) and the VAP11G does the same thing for around $30. This limitation could probably be eliminated with the Asus WL-330gE wireless access point."