Small Form Factor Sensors

I plan to roll out new firewall and network security monitoring platforms for my home lab network. For the firewall, I'm considering an "embedded" BSD solution, like OpenSoekris, m0n0wall, or m0n0BSD, which run on the popular Soekris (mailing list) embedded computers, like the net4501 and the new net4801. I like these motherboards because they're equipped with three NICs. Other Soekris-based projects include FreeBSD wireless router (more info), theWall, Linux Embedded Appliance Firewall, linux4501, Personal Linux Router Project, and Debian on the net4501. The OpenBrick project exists, although the Mini-ITX community seems to have more support, along with vendors like LinITX and Ultim8PC. This CompactFlashTM Type II Card Adapter looks useful.

For the NSM box, I'm considering a Shuttle SB52G (support, review) with Intel 845VG chipset and FB52 motherboard sold by ExcaliburPC, NewEgg, and Knowledge MicroExpress. Crucial sells memory. Other options include the Slimpro 1BayPC (manufacturer?), LittlePC, MicroPC4 and Lex Light, For more information there's the mailing.freebsd.small list, the books Embedded FreeBSD Cookbook and Designing Embedded Hardware, or Slashdot.

One issue with these small form factor devices is having enough interfaces for serving as a firewall or router. Luckily FreeBSD 5.x supports the Linksys USB100TX and USB200M USB NICs. Iomega and others make USB floppy drives. One could always buy a full-fledged but cheap PC from TigerDirect.