The Server Rack: Private Branch eXchange (PBX)

My latest pet project is once again in the one field of Information Technology that I actually enjoy working with: Server computers.
My latest server is an application system built around the Asterisk Telephony Engine and the GNU/Linux Operating System. The whole project got started by happensance: Whilst searching through images for VMware I found out about Asterisk, an Open Source program for managing telephone connectivity. Despite my minimal use of telephones the subject of Telephony holds a great fascination to me. Owing to my somewhat obsessive nature I got more than a little interested in this software, as it gave me the oppertunity to play with a device that I have always found facinating: the PBX.
Building the physical system turned out to be easy: A trip to EK Computer to find an empty case yielded a nearly complete computer. The case, which I purchased for the price of $15, contained a CD-R drive, a floppy drive, a 450-watt power supply and, very surprisingly, a 2-way SMP Pentium-III motherboard with a pair of 500MHz processors! All that was needed was some memory (which, after some scrounging and a surprise find at Goodwill, turned out to be 512 megabytes) and a hard disk.
Installing the software was the easy part: Digitum (the creators and sponsors of Asterisk) released a specialized Linux distrubution named "AsteriskNOW" specifically tuned for the PBX software... After adding a ATA (Analog Telephony Adapter) card and customizing the configurations I now have a working PBX... However as of the moment it lacks any sort of interface to the outside world, severely limiting it's usefulness...
I plan on connecting the PBX to Skype, through which I can have a real telephone number and basically unlimited calling for about $60... A year! However currently the only way to make this connection relies on unsupported software, which I have yet to get working. Oh well, it's been done before, and I have no doubt that I can get it done eventually.

Note: The cases on the rack are (from left to right) Windows 2000 fileserver, Asterisk PBX, a SCSI drive enclosure (currently just being stored) and a power conditioner for the PBX. The left monitor is connected to the server, the right to the PBX.