your favorite protocols

[dmolnar]

Hi, 

In view of the recent thread ("That 70's Crypto Show") turning into yet
another call for protocol building blocks -- and Wei Dai pointing out very
sensibly the problems involved in turning protocols into building blocks
-- I think it might help to compile a list of our favorite protocols and
problems. Then maybe we can see what common components they share, if any. 
Finally see if we can make some progress in overcoming the problems that
Wei Dai mentioned, or if it really isn't worth the bother. 

I can think of 

key exchange			- See P1363 project on this
digital cash			- Chaum
fair exchange, 2party only	- Merkle, Goldreich et al, others
fair exchange, 3rd party	- Micali's "invisible post offices"
anonymous e-mail		- Chaum
anonymous web surfing		- Freedom/Onion Routing/Crowds/Hordes
abuse-free contract singing	- Jakobsson/Garay/McKenzie
middlemen and contracts		- Franklin and Durfee

what else?

-David