I am working on an application that allows you to download OSM data, explore the content and export it. The main idea is that a user can download data for a specific extend (a project area) and see what kind of data is available in this area. Geometries with Tags that are useful can then be exported to Shape or KML. I would say the project is still in an experimental stage, but any feedback is welcome.
You can find further explanations and the download under http://osm-iq.de/node/5