Engineer-Poet, always one of my favourite bloggers for coming up with, uh, unique notions on how to solve energy problems, proposes we mine fluoride waste for it's silicon content. The result: 112,000 tons of silicon per year, enough to make 48 gigawatts (10% of US demand!) at a cost of about $0.35 per watt, or competitive with your current roof's shingles.
And I keep paying attention to Focus Fusion -- one of the hydrogen-boron fusion proposals out there -- for reasons that really escape me. But if you'd like to listen to a physicist talk for about an hour about what he thinks they can accomplish for a few years' and $2 million worth of effort, the head of Focus Fusion gave a talk at Google recently.
One of the interesting things about FF is they don't require any water input for their ongoing electrical production (just a bit for radiation shielding, they say.) One of the many, many limiting factors on expanding our electrical generation if we only stick to status quo technologies is where we're going to get all the water we need to power nuclear or coal. Already, power plants make up a substantial fraction of the water that gets used by human industry every day.
Or, if this guy's right, maybe we're all doomed anyway.