What is the most obscure or rarest tool you own?

The differential pressure gauge measures the difference in water pressure between the high side (red valve) and low side (blue valve), with the yellow valve allowing bypass between the high side and the low side. backflow valve repair kit

I have a spill plane that my buddy made for me. It may not be that rare in permie world, but it's definitely not something you're picking up at the local big box store. https://www.popularwoodworking.com/article/the-all-but-forgotten-spill-plane/

I also have horribly rocky soil so my rebar tamper that sits in my sds demo drill gets a lot of workout.

A jointer that has been modified to put parallel grooves in wood. Useful in building bat houses.

I'm not really sure which one I would say, either the #113 radius plane, also called a circular ship's plane or a compass plane.  Or perhaps one of the Stanley #45's - both are complete with many extra cutters.

Also have a small collection of Stanley wooden body planes, as well as some Bailey/Stanley bench planes

I have no clue as to the price of the 45's today, wayyyyyyy more than I paid, 30 - 40 years ago I'm sure!


Peace

I have a blacksmith-made T-handle twist drill designed for drilling holes for dowels to pin squared log walls together.

A pair of those big pointy tongs used to move big blocks off ice. I used it to move logs with my tractor instead.

I have a lot of odd tools, this one might be one of the "most obscure" though...
Antique tonsil remover. I bought it at a flea market because it looked cool!

This picture is NOT mine, it's off the net, but mine's this type.

Pearl Sutton wrote:Antique tonsil remover. I bought it at a flea market because it looked cool!

Well dang, I can't beat that. Looking at that terrifying device I can't decide if I need generous drams of bourbon or a gallon of ice cream.

Douglas Alpenstock wrote:

Pearl Sutton wrote:Antique tonsil remover. I bought it at a flea market because it looked cool!

Well dang, I can't beat that. Looking at that terrifying device I can't decide if I need generous drams of bourbon or a gallon of ice cream.

BOTH!