Canadian retailer Future Shop has knocked $50 off the price of the 3DS from now until July 31. Both the Aqua Blue and Cosmo Black models are discounted, online and in-store. If you've been jealous of your friends' growing StreetPass Mii collections, now's your chance to begin building your own!
Actually, since there will be more 3DS buyers than usual at pretty much every Future Shop, you should just hang around there for a while and hope the new owners set up StreetPass while they're still in the store. That way, you'll be able to grab plenty of extra Miis until the police arrive.