The idea is self explanatory, connect an Elk to a turnstile and use a cryptocurrency to pay for entrance. The concept can be used in subway systems, concerts, carnivals, sporting events or any venue that requires pay to enter.
The block chain used for the payment would need a very short block time, for impatient patrons and to keep the entering traffic flowing.
A token from a smart contract can be used in place of the tickets and each facility can distribute their own tokens when patron are entering a limited space venue.
NFC would be a great feature to add to the ELK to facilitate the transfer at the turnstile, I know American Express lets you use your credit card at a few subway stations to enter the train.
Some benefits I can think of are countering ticket fraud if tokens are used instead of paper/plastic ticket.,
Reduce waste by using less plastic and physical tickets that are used once and thrown away.
A universal payment system for entrance fees, so a person can use the same method to pay for a subway or train anywhere in the world instead of having to buy separate fares at each city.
Hopefully this can reduce the operations costs of the facilities, by providing an automated payment and entry system using smart contracts and tokens.