There's some giddyup dolls in the old toy factory southeast of d-city. It's got a bunch of super mutants in it, I'm talking a room FULL of them, I ended up with 13 full giddy ups and countless arms,legs and heads, they all give gears. When I finally got back the the city (walking overburdened) I think it got me about 40-50 gears.

Desk fans, I think.