I first heard about them through Linus Tech Tips. Linus used them to remove labels cleanly and said they were popular with people who enjoyed cheating with Rubik's Cubes.
One camp says to buy a carbide scraper to replace an oil pan gasket and another says to order a plastic razor.
I didn't realize that carbide meant carbide steel until I bought one and opened it.
It scratched my engine block, but hopefully not too badly.
I went to order some and found out that Ace carries them!
Why does everyone say to order them if you can just go to Ace?!
I paid $1.79!