For the product I work on (a connection bonding appliance & service), we've used Soekris devices but have found them to be underpowered compared to newer Atom-based products from Portwell [1] and Lanner [2]. Geode-based products are fine if all you're doing is basic firewall, routing, and VPN stuff. Apparently Soekris is soon to introduce their own Atom device.
Another option is a Linux netbook configured with VLANs to get around having only a single NIC. Then if you lock yourself out via the network, you have a keyboard and monitor built-in and don't have to go find the serial cable in your stuff-you-hoped-you'd-never-have-to-use-again box.
The embedded Atom platform they've used has a total of four 1X pci-express channels. Despite this they've fitted two mPCI ports, two 1X PCIe slots, four 1G ethernet ports, and 2 SATA ports.
So I doubt the ability of this platform to even be able to route packets amongst the four interfaces at full speed, let alone filter the packets at the same time. It will, however, do better than the existing Soekris products.
