MoinMap is some haxoring on a MoinMoin macro that allows the embedding of maps into a moin wiki. The architecture is completely fubared right now and is not too easily extensible but serves a few purposes. The best way to see how it works is to EditText this page.
The following is a call to MoinMap with 'address' '2006.NE.Davis.St.Portland.OR.97232' arguments.
The following is a MoinMap of the PTP node number 351 (well, it used to be called 351, now it's 113) located at the Pioneer Courthouse Square in downtown Portland.
Of course this only works for P-town at the moment as the database driving this takes a fair amount of room and time corraling TIGERs.
In addition to the Python code linking Moin and Mapscript there is a logic layer exposed via a set of xml-rpc calls residing on the same server that do geocoding, node location, etc.
See also GeoWiki.