<UNLURK> I've got an Asus EEEPC (701) which I use with a 3G Mobile Broadband USB dongle (HUAWEI E220). I just used the add network wizard and followed the prompts and voila! it was setup. Works quite well (even on the train - Useful when stuck on Norwich to London line!). I have had minor problems with random disconnects but I suspect that this is to do with mobile coverage and contention. Works well enough for casual web-browsing and e-mail (which is what I use it for). Suspect may not be up for beefier things like iplayer etc. :-)
Hope that this is helpful, Mark </UNLURK>