At LeWeb 2012 today, crowdfunded startup InterAxon announced plans to begin selling Muse -- its brainwave-sensing headband -- to consumers in spring 2013. For anyone interested procuring a Muse of their own, they'll have until December 7 to make a contribution to the startup's Indigogo crowdfunding campaign. Currently, offers of $135 or higher will guarantee contributors at least one headband of their own when the device finally ships.