If you want to create some extra impact when public speaking, don't be afraid to present in some odd postures. My friend Ron Culbertson starts his talk while standing on a table. Another friend of mine Barbara Sanfilippo climbs a ladderwhile on stage. Zig Zigler kneels.
I do a signature story while sitting on a chair and I have sprawled myself across a table to make a point. I have seen speakers doing handstands, backflips, riding a bicycle and standing on their head. Of course, I wouldn't do the whole talk standing on my head, but who knows. . . I might look better that way. hahahaha