Airlines and routes:
-St. Petersburg and St.Petersburg-Sheremetyevo (Tu-134 and 154)
Tatarstan, Domodedovo-Kazan and return (Tu-134)
Baltic Airlines, Local in St.Petersburg (Mi-8)
-Sheremetyevo, Sheremetyevo-Murmansk (Tu-154, 737, A310, Il-86, Il-96)
Volga AviaExpress, Domodedovo-Volgograd (Tu-134)
Aeroflot-Don, Volgograd-Rostov on Don (Tu-134)
Voronezhavia, Voronezh-Domodedovo (An-24)
Tretyakovo, Murmansk-Domodedovo (Tu-134)
Some of those routes multiple times.
Visited (without flying): Bykovo, Vnukovo and Khodinka if you call that an airport.
That's just in Russia proper, lots more in the rest of Eastern Europe and the former USSR