Stupid Question

I know there are no stupid questions, but this one reeks of ignorance.

Our office will probably go VoIP PBX in the future, but for now all I’m looking to do is directly connect two computer users with static IPs by voice over an 802.11b wireless link. One user is on a busy shop floor with lots of noise and stuff going on around him, so a standard telephone handset would be the best way (most familiar) to communicate.

All of the results I find on searches show up ‘multi-VOIP users’, ‘Full PBX functionality’, ‘As big as you want…’. I just want to bridge the phones directly through my network. No InterNet VoIP, voicemail or anything fancy, just a voice connection that works like a phone (rings, or sound notification) on both ends.

I’d think Asterisk would certainly do the trick, but is there any smaller, easier way to accomplish this?