Protesters held in Moscow square
More than 20 people have been arrested in Moscow for trying to hold an unsanctioned protest.
The gathering at Triumphalnaya Square in central Moscow attracted 50 to 100 people.
Among those arrested was prominent radical writer Eduard Limonov.
For about two years, activists have tried to rally on the 31st of each month with that many days, a reference to Article 31 of the Russian constitution that guarantees free assembly.
Authorities routinely deny permission for the demonstrations. Mr Limonov's faction has fallen out with other elements of the wave of opposition to president Vladimir Putin that arose last year.
In his New Year's Eve address Mr Putin made no reference to the protests of the past year, saying only of 2012 that "it was very important to us.
"We believe that we can change the life around us and become better ourselves, that we can become more heedful, compassionate, gracious" he said.