Latest High performance engine

[sno_duc]

Lethe, was your garage a machine shop in the 10's or 20's? that looks like a variable speed take-off from a main line power feed. (very cool) one motor (much like the one that started this thread) ran a shaft that would run multiple pieces of machinery.

Three speed, notice the 3 stepped flat belt output pulleys.
Reversible, the 2 pulleys with the grooved collar in between are the input pulleys, the curves "arms" with the jam nuts are some kind of clutch. (the one on the left is probably engaged)
That set-up was placed ninety degrees  to and below the main line shaft and the belts were laced such that the input pulleys spun in opposite directions.
Also notice the pulleys are "crowned", to keep the belt centered.

[koko64]

Some hard looking rigs there. 

[lethe]

now you make me want to get it down out of there even more

I have a bunch of old stuff that I want to set aside a corner of the garage for as small museum of sorts.
That thing, an old drill press (a Canedy Otto E20), the old foot operated sewing machine from my father in law's shoe shop and various other oddities.

[Ducatamount]

Sounds like you have the begginings of a cool little industrial collection.
Those drive shafts are very common around here as they were used by many types of wood workers. Lumber mills, furniture makers and more all used them. They usually had wide leather belts stapled into a loop as belts. They ran at a fairly low RPM. Belts could be slid sideways off the pulley wheel to sit slack when a certain machine was not in use.
Sometimes you still see signs/shreds of the leather belts but usually they're disintegrated or eaten by critters.
Yeah... be careful dropping it.

[freeclimbmtb]

not a motor but I do have this thing in the attic of the garage. i should figure out a way to get it... ...down

Just cut the floor joists.  It'll come down.

...safely...

Don't cut them from below?