I learned this in the early 90's from the Kaufman book on Paul's magic, Steel and Silver. It's a great coins across into the spectators hand, using their finger ring.

I've used U.S. quarters, English pennies, Kennedy halves, African pennies and Eisenhower dollars.

I din't think it really matters what coins are used, but I've started using Kennedy '64's again. They're shiny and catch the light so well.

Anyone do this routine and have a coin preference?

I use Morgans. How well do you do with the spectators ring? I've been caught a few times.

Doug Brewer has in his Unexpected Visitor book a nice variation using a chinese coin instead of a ring. You get a very clean transpo with the last coin. A little bit easier than using a ring.