[crypto] crypto-protocols for trading card games

[Simon Spero]

Here's an interesting problem:

In the not too distant past there was a fad for collectible trading card 
games, the most famous of which was Magic, The Gathering (tm). These 
games combined the collecting and trading of baseball cards with traditional
aspects of card playing. Cards were issued by a central 
authority/publisher (Wizards of the Coast in the case of MtG). Each 
player uses his or her own deck; cards that are not played remain secret; 
however the same deck mut be used in each round of a match. tournament 
games are adjudicated by an umpire.

Design a set of crypto protocols to support the issuing, trading, and 
playing of such card games in real time (100ms compute time per move)

Simon