I think I know what picture the OP is talking about (but I can't remember where).

As I recall, the lever was positioned where most people put cross levers, right next to the stem. The only difference was that, instead of a clamp around the bars, someone figured out a mounting bracket that lined up with the two bolts on the faceplate of the stem. It's actually looked pretty good and functional. The only downside is that I don't think you would be able to adjust the rotational position of the lever at all.

As far as I know, that was an after market modification of some type of road lever. I think if a brake lever like that was actually manufactured, they would be much more common.