Over seven hundred slides from Peter Gutman’s Godzilla Crypto Tutorial. I imagine aliens flipping through this in about thirty seconds to absorb all current knowledge regarding the uses and abuses of crypto. Not particularly mathematically heavy-weight, but pretty techie in parts. The seventy-one slide guide to crypto politics is pretty comprehensive (not entirely up to date though). I got this from the enhyper financial crypto digital library mailing list, which occasionally turns up some great resources.
Currently:
gutmann’s guide to everything crypto