A friend of mine, Chris Joles sent this one to me. Geekdad, from the eponymous web site, made a burger of 100% ground up bacon and added an egg to help bind it. He cooked it under the broiler so the drippings didn't mess up his grill.
His conclusions, try one, don't make it too big, use uncured bacon to reduce the salt content, have it with a strong beer, enjoy. It is not meant to be a weekly repast, but a nice change of pace from the ordinary meat burgers. Mmmm I may have to make one to see if I agree.