Would pfsense look into USB 3G devices? Since it is becoming more and more widely and cheaper available. Would be great since in Hong Kong the speeds have reached 21Mbps download and 2Mbps Upload. Have two of it running as dual wan would be really interesting. Finally can have a truly mobile server solution LOL ;D Naturally there is no fixed IP available but dynamic dns works great.
There is some support for 3G devices in 2.0. I don't recall the specific models supported, however.