CMT 2050 blade cleaner! It's almost pleasant to use, non-toxic,
and works like nothing I've ever tried. I've also used oven cleaner
(too strong, strips blade markings, not so nice to humans), washing
soda (works _OK_,
but slow), kerosene, Simple Green, etc...
I don't sell ANYTHING related to woodworking, nor do I have anything
to do with CMT.
Thanks to Leon for the tip.