The flight into the ruble?
Russia is still a very murky and dark place, as far as understanding domestic economic policies. That said, the strength of the Russian ruble against the dollar-euro basket is impressive.
Given Russia's rich natural resources, demand for the ruble is in a certain way understandable. But, it also signals that the Russian central bank is not printing excessive amounts of new rubles. Nothing can kill a currency's strength like a central bank running the printing presses.
It is not for conservative money, but someone with high risk money may want to consider placing a bet on the ruble.