Tipping is increasingly encouraged in Russia. 10 to 15% is the accepted rate of tipping for restaurant servers.  For coat check and luggage attendants, anything from 20 to 50 rubles per item is acceptable, although many people don't tip them at all. Tip drivers or tour guides $10 per day or more, and housekeeping staff the equivalent of $1 to $2 in Rubles, usually left in an ashtray or on your pillow daily.  Note also that restaurants do not allow you to add a tip to the credit card charge, so even if you are paying with a credit card, the tip must still be left in cash.