Waltorious: I only played one of these, a long time ago... if I remember correctly, it was The Even More Incredible Machine, which sounds like it was probably the second game in the series. Anyway, it was quite a lot of fun. It's funny, because nowadays there are lots of physics-based puzzle games showing up, from simple flash games to games like World of Goo, but these games were doing physics-based puzzling long before anything else I had seen. And it's pretty impressive for the time: different types of balls have different weights and bounciness, conveyor belts, cannons, and bounce pads all work like you'd expect. I was always surprised there weren't more games that tried this formula, until now.

One downside that I remember is that some of the puzzles could be a bit finicky. Often my design was basically sound, but it wouldn't quite trigger things right and I had to mess around with nudging objects slightly until they finally worked. But this could also be seen as an advantage, because I have a feeling that many of the solutions I came up with weren't the ones the designers intended.

My favorite feature of the game, though, was the sandbox mode where the player could simply build some crazy contraption just for fun. Mine inevitably involved a ludicrous number of bouncing balls going in all directions and causing complete chaos. You can also use this mode to design your own puzzles, I think, which can be shared with friends. Pretty cool.

Also, the GOG version claims to include all the game content without any redundancy, which is good. These were games that were often re-released in different packs and it was hard to determine whether you were actually getting any new stuff or just the same stuff you already had, rebundled. The GOG pack sorts all that out for you which is very convenient.