Mobile broadband providers

I was just wandering if there are any mobile broadband providers yet that let you surf the internet while actually moving on the road? I know of at least one that you can surf while parked, but I don't know of any that are able to let you surf while moving. If anyone knows of any ISP's that offer this, please let me know. Thanks.

In my home town (smal town in Iowa) we have wireless boradband that's alright. The service guys said they have used it while driveing. They had to rotate the antena iby hand thogh cause it's line of site.