This very basic, lightweight displayer is completely hacked together - but it works. 

The UI is not very sexy, but I figure that's ok since you only have to use it once. 

After you walk through the wizard you receive some Javascript you can embed in your blog or elsewhere (see mine at http://opencontent.org/blog/ for an example). 
The widget currently:

- shows up to the first four badges in the group you selected,
- badge images link to the hosted assertion, and 
- badge names linking to the badge descriptions.

I'm sure you'll manage to break it, and I would love any feedback or ideas for improvements!