I make a lot of crępes and I've never wanted them to be anything other than what they are. I'm trying to imagine what you would *do* with crispy crępes because their very nature is to fill and fold and that pillowy goodness of them makes them special. I'm not very creative, so I'd love to hear how you'd use crispy crępes . I love a new use for an old standby.
To answer your question, I think if you want them to be crispy, it's going to be a 2-step process. I would cook them as usual and then let them cool. Once cooled, brush liberally with butter (if sweet) or oil (if savory) and then pan fry them. With enough fat, they should crisp before they brown excessively.
Honestly, though, you may explore how to make thin savory waffles because they are much more crispy... or at least to use a waffle iron to make these.
ETA: my crępe batter is 1 c. milk, 1/2 c. flour, pinch of salt, 2 eggs, 1 T. melted butter.
Life is too short to eat processed, artificially-colored, chemically-preserved, genetically-modified food. Or maybe that IS why life's too short.