1. Dr. Heard
Dr. Heard may have lacked some of the showmanship of a Bill Nye but he amazes nevertheless. Notice that none of the audience members is anywhere near his demonstrations. That's for a good reason.
2. Steve Spangler
It would seem that Steve Spangler's appeal would be broader than appearances on some local affiliate's morning show and the occasional (expensive) gig at a school or museum. I'd watch his show if he had one! Maybe he's doing well enough with his online store that he doesn't need the hassle of producing a weekly program.
3. Robert Krampf
I did this demonstration with my students. The tension in the room as the kids wait for the water balloon to pop is palpable! When there's no big explosion of water and latex, I think the kids are a bit disappointed, but their curiosity is piqued nonetheless.
4. Bill Nye the Sci-Fi Geek
What science day would be complete without Bill Nye...re-enacting one of his favorite scenes from what could be his favorite movie (for all I know.)
Where did that carboy (big glass jug) go!?