A 1u box with an intel core i3-2120t (35w TDP) machine. The atom 1.6 Ghz box I had before wasnt quite fast enough to handle VPN at the speeds I needed which I use for the bonding. -- 150/75 mbit Verizon FiOS connection FTW!
Linux since that is what I am intimately familiar with and not even sure if there is a packet based round robin bonding driver for bsd so not even sure if I could do what I am doing on bsd. -- 150/75 mbit Verizon FiOS connection FTW!