Yup I've heard leaf springs make some good tools. I also might have an old blade from a table saw that I'm considering.
I only ever really work with very hard woods (massaranduba, Ipe, ash, balau, garapa, etc), so I'd like something that can hold an edge. Nothing more tiresome than reducing 1/2" off an entire massa belly, ha ha.
Let me know how yours works. I'll definitely investigate it!