APRS2ATM (also known as a2a100.exe) is a small bridge application that connects to the shared memory objects of the commercial iGage All Topo Maps mapping program for Windows and feeds it "annotations" created from APRS data it obtains via an APRS-IS-style server port or directly from a TNC. It can be used to add topo map capability to any APRS program that provides a server port (e.g. APRS+SA OziAPRS, UI-View or Xastir).
It can be downloaded for free from its author's web site. It is known to work with versions of All Topo Maps up to the current version, Version 7 Pro.
Here's another page that talks about it and similar types of software: APRS2ATM
In January, 2010, Tom Russo, KM5VY, released a minor revision of APRS2ATM called a2a101. a2a101 adds parsing of APRS objects and Base-91 compressed positions to the parsing capabilities of APRS2ATM. It is available in binary and source form at the web site of the New Mexico Search and Rescue Support Team under the "Software" link.