Probably a hot water heater, chistmas decorations, and some photos Jim wishes were never taken. :P

Realistically, the only really hard parts of making a nuke are getting your fissionables, and machining them without killing yourself. And the latter isn't really that hard, just expensive.

Of course, if you want simple, two masses of U-238 or Pu, literally in the hands of someone with a death wish and a very high pain tolerance, qualifies as a nuke.