Chasm
A game I found while spelunking on the 'Net.
Basically, you're some sort of weird platypus being living in some backwoods Western town. There's a thing that gets water to the villagers that somehow stopped. They need to get it back before six o' clock to watch the Big Game of some sort, so they send Dan, the laziest guy in the village (aka YOU), to go fix it.
Note that the game structure is vaguely MYSTian. Not nearly as fiendishly difficult, but with that same sensibility of solving puzzles, flipping switches and pulling levers, things having direct and indirect effects on other things, and so on.
And no, I haven't figured it out either, although I'm getting closer.