I'm making a new table that is going to have a somewhat unorthodox design. Anyway, I saw this picture and I thought that I really liked the heightening-/lowering thing, that I have encircled... Just one qustion though; do anybody know what these are called??
What you're looking for is a screw jack.
And that is a industrial crank table, much nice in blue in my opinion.
How about a trailer jack, one mounted on both sides should do the trick, though perhaps not as attractive.