Several people have commented on the lack of a windshield pass-through location for a toll transponder. It is supposed to be to the right of the rear view mirror, but most of us have found that it is intermitent at best and our windshield has no spot where it will work. We travel constantly on toll roads and bridges, so searched for a better spot.
There is a ready made location behind the car's plastic nose. The nose cap pops off with a little pressure under either of the lower corners. I used a towel-wrapped flat screwdriver to pop the first panel release. There are standard body panel press-fit attachment points around the panel - they won't break - be forceful, pry outward and it comes right off. Pry only under the shiny black plastic, everything else stays in place.
Interestingly, there is no space immediately in the front part of the panel. Although some on the forum have suggested they don't like the protruding nose (and a few say they plan to replace it with a grille), it is shaped this way to cover a heavy steel crossmember that forms the front of the car's crumple zone. I like the way it looks anyway, but there is no potential to install a fat or recessed grille or other cover. There is about 1/4" between the steel beam and the cover panel, so no place in front to put the pass. However, to the left and right of the beam there is a recess, with a flat steel plate that is the right size to hold an EZPass transponder. A little industrial Velcro, job done!
We had a license-plate mounted EZPass transponder on a prior car, but it is an ugly black bar, and we don't have a tag on the front of the Model S, so prefer the hidden method. A couple pictures here: