I hope it doesn't sound like I'm advertising for them. These may be complete crap - I haven't used them yet. They are an interesting idea though. Similar to Newk Barends. The guy who made those died, so that was another option that disappeared. As far as I know, no one else makes a similar product at the moment.
Here's an old post. This dude eventually did the full drop-bar conversion for significant money (that may say something about how effective the road ends were - the new versions look less goofy and sturdier than these old ones though...)
Road Ends:
http://www.cyclingforums.com/t-195911-15-1.html