I don't know about "modules" for embedded projects, but my Sony GC-79 
card works great with any GSM SIM card I've put in it that had "data" 
service turned on by the carrier.

It's interface to the host machine (usually a PC, but... perhaps someone 
enterprising could use it in something else) is PCMCIA.

It also has 802.11b on-board and both cellular and 802.11 can be active 
at the same time.  The windows driver/GUI interface the carriers provide 
avoids doing this, but driving the card directly under Linux, the 
hardware certainly allows it.

Anything that worked with the standard pcmcia-serial drivers on Linux 
could talk to the "cellular modem" where you just send some non-standard 
"AT" commands to connect/disconnect from the cellular network's built-in 
ISP service via PPP, and the 802.11 was a standard Broadcom chipset 
802.11 card.

I think they have a later version out now that changed to higher-speed 
802.11g support for the WiFi side of the card.  The newer version of the 
card (this one's not available anymore) also was EDGE-capable for higher 
speeds on the cellular network.

Nate
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