There is a relatively new product by Texas Instruments – the SimpleLink CC3000 WiFi module that is quite small and cheap – $12. Looks quite promising, size is about as much as a fingernail:
There is a KickStarter project using that chip already, quite intriguing. There is still no library for Arduino, but I guess it is just matter of time before one appears. There is an initiative here.
Other projects (in progress) that use that chip are the WiFiduino
..and a CC3000 shield project:
I will keep an eye on these projects, WiFi is something I long wanted to include in my projects.
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