Each person non resident of the Russian Federation prior to applying for visa in the consulate must get an invitation according to the purpose of his or her visit.
Your Visa To Russia provides invitations for tourist and business trips.

Roar: opposition activists go green and musical

Members of Russian opposition groups not represented in the parliament have staged two rallies in Kaliningrad and Moscow on the weekend and supported the efforts of ecologists to defend Khimki forest.

All Russia news »

Source: http://rt.com/Politics/2010-08-23/roar-opposition-activists-go.html