Accessory for 3g on Ipod touch?

Is there any accesory for the ipod touch 2g that lets me insert a SIM card with the data plan and use the internet as if it was with an iphone? Maybe attatched to the connector on the bottom?? anyone anyone?

If you want 3g service on your iPod, your best bet is going to be one of those portable "hot spot" devices like MiFi. Here is an article that talks about those mobile hot spots -- Guide to 3G and 4G Mobile Hotspots and MiFi Technology | Mobile HotSpot