In part of my quest to simplify my life I moved away from Windows workstations and servers to Macs. With the number of systems that were removed it had a large impact on the acoustics of the room as well as power consumption. I still had one relic left behind and that was a firewall running on a PC to keep my IPSEC tunnels up with all my clients. I decided I could replace that unit as well with something that was at least fanless. During my research I found something that would be fanless and work with a 15w power adapter so it would have a small electrical footprint. The hardware I used was a PC Engines ALIX 2c3 board on which I installed the m0n0wall embedded firewall OS. I also used a Soekris VPN1411 mini-pci card to offload the encryption processing from the CPU. It is very small and runs super smooth on a 30mbit connection with 10 tunnels running. The CPU never goes above 40% utilization on a full load. It is fairly inexpensive and quite simple to assemble and program. I am in the middle of doing a video tutorial on putting one of these together and programing it. I should have the video done along with support pages tomorrow, so check back.
UPDATE: An updated tutorial has been posted here: http://www.techunplugged.com/2009/07/22/alix-monowall-firewall-part-1/