An annoying thing with the 3G data dongles is that they do not work with all USB devices. A good many mobile devices include Wi-Fi so a router that accepts a 3G modem and shares this out over Wi-Fi would make for a useful accessory, add a battery so it is mobile and you have a lot more options for where you can use the device.
The Wireless Router for 3 Mobile Broadband costs £69.99 when purchased with one of the 3 mobile broadband dongles. Beyond the basic price and options of a black or white model there is little other info apart from the fact the device is tied to the 3 service.
3G routers have come down in price very quickly as mobile broadband dongles have increased in popularity. A quick search online reveals a number of devices available in the £50 to £90 bracket, including the Billion 7402GXL router, which offers both support for 3G modems and ADSL2+, with automatic fail over from ADSL2+ to 3G.
3G routers also will allow people to position their 3G modem in the optimal location in their home, if using mobile broadband as their main broadband service. Though for many a cheaper solution will be to see if the modem works over a USB extension lead. If using a 3G router to share the connection it would be wise to ensure you have security switched on, otherwise a 2 or 3GB monthly allowance could vanish over night.