I see you got the fan for free and most of the cost was in the suit case you used, which was cool by the way. But just to let you know, for $12.50 you can buy a USB fan which already has the rheostat built in
so no wiring is necessary. All I did was remove the legs, cut off some of the grill in front to mount a hard drive magnet to the fan, and used shorter screws but this probably isn't necessary. I also added a USB adapter that had an on/off switch.
You can't quite see my stir plates, but here they are in action on 2 yeast starters.