Back in the 1980s I used to read Omni magazine. In the 90s, it was magazines like Wired, Mondo 2000, and Boing Boing. These all presented views of the future that I found interesting and (mostly) hopeful - even if a good percentage of their articles had no basis in reality.
Today, they're all gone or nothing like what they used to be.
What magazines, blogs, podcast, etc. do you use to discover possible positive future technologies?