From CoolHunting

Eye Fi card

“By installing Eye-Fi software on your computer and using the 2GB card in your camera in place of a regular SD card, you can use your home WiFi network to automatically upload photos via easy-to-use software. It’s really that simple.”

Slight downside that you have to install software – I hope this software can be downloaded for free from their website for those times you’re in a cafe, or perhaps the software only enables extra features like uploading to Flickr etc.