John,
I feel your pain. [Linked Image]
A couple of years ago I dropped a brand new pair of Klein angle-type diagonal cutters down the back of a wall oven cavity while working up in a roof-void.
I could see them down at floor level and even managed to hook them out with a length of catenary wire, but as I was lifting the hooked wire out it turned and the cutters fell off, only to drop to the floor and roll under the oven unit. [Linked Image]
The oven unit was built in to the wall and there was no way that I was going to tear the cabinets apart for a pair of side-cutters. [Linked Image]