We have a Canon 7D camera with the EYE-FI-4EV card (red Wi-Fi 4GB card). Naturally with the 7D, we had to purchase a SDHC to Compact Flash adapter. We chose this one from Amazon:
http://www.amazon.com/SD-CF-II-Type-Ada ... B000YZGCIU
My office is down the hall about 50 feet from the WiFi hotpot in our building. With walls and such, WiFi isn't always very great on a laptop in my office. I first tried putting the Eye-Fi card into the adapter and gave that a shot. It did work, but the uploads for a 6MB JPG were brutally slow. So, as suggested everywhere, I easily removed the metal front and back from the adapter card:



The metal back had a thin plastic paper between itself and the chips, so we cut a very thin piece of flexible plastic to attach (tacked in corners with tiny amount of super glue). This would help protect the chips and provide rigidity.

With the metal removed and the plastic in place, the cards works great. Even with a weak WiFi signal in my office, the uploads were much more reasonable. If I went down the hall to the vicinity of the router, uploads were very fast. So far, we are very pleased with the results. We will be using it to show RAW and low res JPG (still huge) simultaneously and then upload the JPG to Flickr that is then immediately sent to our website. Thanks to the camera buffering, even high speed shooting works fine with the RAW. Videos? Well, forget it. HD records for about 3 seconds and then stalls. It did seem to work at 640x480 but for any video purposes we will never need the WiFi uploads anyhow.
So, I know, we aren't supposed to be doing this, but it does work.
