So one day I was messing about with pistons, and I was struck with inspiration when they reminded me of the disappearing blocks in Heatman's stage from the classic NES game .
On that note, obvious disclaimer is obvious: Capcom owns Mega Man and all associated characters, maps, etc. This is an homage, and my only contribution is extrapolating a classic 2d map into 3d. If you think jumping on disappearing blocks over lava is the best idea ever, thank Capcom and Tokuro Fujiwara.
So I went into Creative mode to see what I could do, and when I was done, sent it to a friend who's into romhacking; he said he loved it, so I figured I might as well share it with the forum. The basic idea is to use blocks and gimmicks similar to what you find in Heatman's stage.
That means a lot of red brick (thankfully we have two types, now!), gray stone, and magma. The main gimmick in Heatman's stage is making precarious jumps over magma or bottomless pits, sometimes stepping on blocks that appear and disappear in some set pattern; this is accomplished using lava, open pits to the Void, and pistons run by redstone circuits, respectively.
I should admit that I did this in Creative, and haven't figured out a way to add enemies without extensive custom modding, or to shift it out of Creative mode. As a result, it won't be hard to cheat or break the map. A bit unprofessional, I know. If there's some easy way to do that, I'd love to know about it. Otherwise, it's not that big a deal. It's done in 1.9pr5, though, so some things may work wrong (or not at all) in another version.
As a note, yes, I did actually try it myself. I found there were a few spots where it's definitely challenging; it can be a lot harder keeping up with the moving blocks in 3d than in 2d, and one of the jumps was just too much of a "jump at exactly the right pixel" thing and I had to make it easier. But it can in fact be done.
PS: Comments are, of course, welcome! If there's a positive response I might look into building other Megamancraft maps like this. I considered Quickman, but I can't get the laser mod to work for me. I've got some ideas for how to do a sort of Brightman map, also.