I finally have a working 1.44MB floppy drive in my Mac SE... after two previous failed repair attempts last year 
Spent much of the day cleaning, greasing, and changing out the gears on the eject motor. Unlike the last drive I tried with, this one actually powered up and booted the system. So the SE is off the repair bench and back home on the Tower of Power!
I've amassed quite the collection of broken floppy drives though:
- Mac 800k that originally came with the SE, needs cleaning and a new eject gear
- Mac 1.44MB, mechanically working great but has an electrical fault
- Amiga 880k, needs cleaning, also PCB had a leaky cap and there's corrosion
Also, while I had the SE open, I installed the MacEffects Performer 030 accelerator PDS card and it's a speedy boy now at 16 Mhz. Not as fast as the IIfx but fast enough that I'll probably upgrade it from System 6 to System 7 sometime this month.