I tend to give an inane non-salute wave back, which I realize may invite trouble, too, since it projects a "this may be a vulnerable human" visage instead of my usual "unpredictably eccentric" (or "oh, that's just Sue") one. The finger might actually send a better message (sounds like a doctoral dissertation! Let's do the research...)
I still can almost sense the "oh! a bicycle is there!" perception sometimes , and I hope that that gets logged into the memory and the next intersection that person is just a little more likely to recognize a bicycle image just a little sooner. (It's how things work in my brain.)