Hi Chunk,
It's certainly possible, but it will require a bit of javascript coding into the template files. You might take a look at the DotNetNuke Map project. While you can certainly embed google maps within your Repository templates, it might be be considerably easier to just have a "link" on each repository item that will redirect the user to a page with a Map module on it and have the business address displayed.... I haven't done that but it should be possible. 

In the meantime , I will take a look and see if I can work up a version of the business card template that includes a Google map. It's a great idea and I think most people would appreciate it.

If you haven't already, refer to this page for details on embedding a Google map on your web page.
http://www.google.com/apis/maps/documentation/index.html

It's not difficult to have a link to Google maps, you just need to get the lat and long etc. Not the best but it will work for now. I am happily looking forward to what you come up with!