Bob Came in Pieces is a physics-based puzzle game with levels; you could call it a platformer, as solving each level involves traversing a 2D space where upward motion is often necessary, except that no jumping is involved. Bob is a sort of space ship, and you move by using jets pointing down and to the sides, in an environment where gravity is always downward.
This is, in fact, one of the awkwardnesses of the game; Bob is often hard to control, and you can even wind up stuck in a nook you can't blast yourself out of. The Enter key takes you to the last save point, so trapping yourself isn't permanent, but it's a little clumsy.
Because it's physics based, puzzles often involve doing things like moving a gate or ramming into a bunch of crates hard enough to tumble them over. This aspect of the game feels quite a lot like Little Big Planet, actually, and there's enough variety in the puzzles to keep you entertained.
Where Bob is quite different from that game, however, is in the fact that Bob is customizable. Each level, you collect some number of spaceship parts -- the story is that, like Captain Olimar of Pikmin, you've crash-landed on a strange planet and must rebuild your craft to escape. At various points on the level are places where you can enter workshop mode, which allows you to attach parts to your ship, and move them around. Thus, for example, one puzzle requires you to poke something through a small opening to free up a path; another requires your ship to accelerate with more power than your original engines provide. Entering workshop mode, you can add a long pole to your ship, or strap on another engine.
This element of gameplay is reminiscent of Fantastic Contraption, except of course that FC is much more of a sandbox game, and allows players to create far more complicated devices. Still, between the physics-based platforming and construction-solvable puzzles of Bob Came in Pieces, there's obviously a very large design space and a huge potential variety of puzzles.
Indeed, Ludosity recently released a new set of levels for the game, available for free to previous purchasers, an indication that the potential has not been exhausted.
It's polished, well-conceived, a little awkward to control, but quite nice, on the whole. Mac version, too.