As of Apr 29, 2008 Aeroflot's best price is $45 one way not including taxes and fees. Adding taxes and fees it comes to $81.60.

You can buy a 2nd class train ticket at the train station for $35 cash according to www.waytorussia.net.

If you take the night train, you can save yourself the cost of a hotel room which could easily be $135 - $200. Though, a plane might be safer since people have been known to be robbed on trains.