You ride a little car past various chocolate-making machines
How would the ride move?
Also, I’m planning to definitely build a magnetic ice-skating pond.
Deborah Higdon-Leblond is one person who did this. From what I remember there is very small tolerance between the upper and lower magnets, you have to balance friction with the attractive strength determined by the distance between the two magnets. From what I’ve seen, the hidden magnet rides on a chain underneath the surface.
It would be nice if the magnet attached to the minifig did not encounter “seems” of adjoining tiles. Perhaps an inverted 16 x 16 clear baseplate would be a got surface for the skater to slide on. However, if you want to use tiles on top, the LEGO store PaB’s currently have lots and lots of 1×2 trans light blue tiles.