There are some programs available with similar functionality, such as
iptraf. This can certainly show you other machines' MAC addresses. Can't remember exactly what it logs (at work at the mo', and don't have my Eee with me). There is also
Wireshark of course, and if you did want to build your own you could use the source code of these as a starting point.
You may hit a snag, though, depending on how your machines are connected. If it's through a passive hub, each machine will be able to see the traffic between all the others. If it's a switch, on the other hand (and most "hubs" these days are switches), the machine will only be able to see its own and broadcast frames.
