The Google Maps API for Flash provides a new way to add interactive Google Maps to your website, using Adobe's Flash® plugin to display dynamic map content! This API exists as a fully independent alternative to the existing JavaScript Maps API, and provides many of the features of that API while also adding the ability to mix Flash content with Google Maps. http://code.google.com/intl/en/apis/maps/documentation/flash/intro.html
ModestMaps
Modest Maps is a BSD-licensed display and interaction library for tile-based maps in Flash (ActionScript 2.0 and ActionScript 3.0) and Python. http://modestmaps.com/
The all-new Yahoo! Maps component for Flash and Flex 3 enables you to add a map to a wide range of web and desktop applications. Included in the API is support for other Yahoo! APIs including geocoding, local search and traffic APIs along with an advanced marker and overlay system to allow you to easily render geo-data on the map. http://developer.yahoo.com/flash/