There are two in my building (including me). The other is in his mid 40's, I'm 32.

A new one I met this morning from the building next door (est. 30's).

There is at least one at one of our other offices down the street (no idea who it is, just an REI Randonee).

I saw 3 new commuters on the way in this morning, all sidewalk riders, but at least they're riding (I'm guessing ages mid 30's through mid 40's).