Cloud-based storage provider Dropbox has revealed that it could start incentivizing its users to improve security on their accounts. The San Francisco-based company currently offers new users 2GB of storage for free, then charges $10 per month for 1TB or $15 per month for unlimited. While the company would clearly love as many of its 400 million global users to upgrade to a paid plan, it seems Dropbox could offer a little bit more for free on the condition that users turn on two-factor authentication.