What's the exchange rate between pounds, rubles, and dollars?

A pound of rubles equals a dollar.

UPDATE: Commenter brettbelmore adds another one:

You should keep all your money in Rubles…. It will be safe because nobody would expect to find money in a sack of Rubles.

FURTHER UPDATE: From my colleague Steve Yeazell, a joke that the New York Times reports is being told now in Russia:

Q: What in your life would you most like to change?

A: Rubles.