Now this is just bizarre: Challenger to Putin for Russian Presidency Is Missing. The guy was expected to garner maybe 1% of the popular vote, so it's not like he was a serious political threat. I'd say either he knew too much about organized crime infiltration of Putin's government and he had to be silenced, or he saw himself making a 1% scratch in the Putin machine and thought that if he "disappears" until after the election, more voters will have second thoughts about continuing to support an increasingly nepotistic and criminalistic regime. Who knows? Maybe he'll double his effect, and 2% of the voters will vote for him, despite his having gone missing.

[UPDATE: 040210 - He's been found. Says he just decided to take a break. (Without telling his wife or campaign workers or anyone else. Hmmmm...)]