The recent thread on machinery skates had me browsing McMaster Carr's web
page. I'm familiar with the normal kind of machinery skates (they look like
a tiny army tank), and my local tool rental place has them for rent for $13
per day each. The problem is they are about 4-5" high and I can't lift that
much with a pinch bar.

McMaster Carr has inexpensive "roller ball miniature positioning plates"
which are about 1/2" high and appear to be ball bearings contained in a
steel plate. Go to mcmaster.com and put 5764K31 in the search field. Has
anyone tried to move machinery on a smooth level floor using these?