I've always been somewhat partial to the stellarator design, I mean a big plasma donut is cool and all, but what if we twisted it around a whole bunch first!?
It has density issues though. If you had a piece of the sun the size of a huge power plant - like enormous, the power output would be too low to be useful.
Mandatory: We should build it in space and beam the electricity back to earth using electromagnetic waves. We could collect those using solar cells. And then get rid of the plant and use the sun instead.