DT levers as bar end
 

I have set of 7700 Dura Ace bar ends, but the right one went fubar, literally partially fell apart. It was only working on friction, before that. I had, on hand, a set of 1050 DT levers for 6 indexed, or friction mode. I looked at the mounts for the levers, and they appeared to be exactly the same. Ego, I went ahead and tried the DT lever as a bar end, and, no surprise, it works just fine in friction for up to 10 speeds. My surprise in doing this is finding that I like the ergonomics of the DT lever much better than the bar end lever. I rarely use the bike they are on, and am giving it to a friend with a different bar and levers. If not for that, I would replace the left bar end with the 105 left DT lever. I was just messaging with a member that is looking for a left bar end, and I offered mine up. I like the bar ends on some set ups, but I will have nothing I want to use bar ends on. If the forum member passes on the left one, it will be available.

I think I beat you to it. :)
In the late 1960s / early 1970s I played around with downtube levers at the ends of drop bars.
I think my favorite barcons are still the first-generation SunTour non-indexed ratchets.

They work just fine but are longer than traditional bar ends and can spike the knees of taller riders when climbing out of the saddle.
That hurts.

Totally agree. I’m using downtube shifters as bar ends on my miyata and cannondale touring bikes and really love how they feel. I actually like them more than the bar end shifters on my trek. If your knees come close to the ends of your bars, you can look into a wider bar or some flared drop bars.