I was once said that my Dolly was my worst tool but my unsung here is my set of Crow's Foot Wrenches.
Ironically I didn't discover them by chance until several years ago, but they have been highly successful in helping mr apply a lot of torque to hard to access areas you just can't access with ratchets or sockets.

My other unsung hero is my 6" Pitman Arm puller. It wan't Harbor Freight! It was strong heavy and well made and I have done all kinds of front end work with it and its been a real life saver.

My last unsung hero is my Hobart Mig Welder which has paid for itself already on exhaust work, body work, and last week I stripped some flywheel nuts; welded new ones to them and got them off!.

Also post a link to a nice Tool Catalog or Supplier that you have done business with. Not Craigslist or Ebay! I loved the days before the Internet when we would get mass mailings of Tool Catalogs!