Monaco
The Monaco project was as strange as it was hard to run. It evolved around an idea called GSM Light but was carried away with a donation from Ericsson. The original idea behind GSM Light was to keep the GSM cellular terminals as is but to replace the back-end protocols with SIP and VoIP. A GSM Light base station would look like a GSM network in the radio interface but as a SIP client on the fixed size.
The problem when exploring ideal like this is that while it's easy to experiment in the IP world using regular computers, it's close to impossible to buy a mobile network to play with. This all changed when Ericsson donated a container with a complete GSM/GPRS system inside.
We parked the container behind the Forum building and soon had it up and running with a lot of help from Ericsson people that took a long lunch to help us configure the system. A project with Axerra allowed us to operate a ISDN channel over a routed IP network so we could have one base station on the roof of the building and using the regular KTH IP network to connect to the container. The link was robust enough that we could have had several base stations all around Sweden and even in other parts of Europe. This now opened the possibilities of operating a GSM network from KTH with base stations located at other universities.
The Monaco container was extremely useful as an education tool and was used in several courses. The problems involved in maintaining a mobile network was in the end too much to handle. In 2006 the system was closed and has since then not been in the air.