I almost forgot to mention ...
I was doing some last minute "shopping" with my daughter who wanted to get something special for her friend at an antique store.
Of course I always look at tools, records, CDs and blades when I hit one of these places. I never look at toys, but there was a nice box on one of the stations. I looked.
I found a magnetic dado shim set with all twelve shims, complete. It was marked as "toy magnets, probably from old speakers" and yet they were in a nice wooden case. It was three bucks!
There was no brand name on the box set so I assume it was a part of a complete dado set at some point, but when I got home I pulled out my micrometer and measured and, just as marked, each was as precisely sized as it could possibly be.
AND, magnetic!!! Which means that altering the dado width by a few thousandths at a time is so much easier because the shims "stick" to the plows as you replace them for more precision in cutting.
I have no idea what these are worth, but three bucks for "toy magnets" seemed like a no brainer to me.