Tesla invite teases 'the missing piece'

Tesla has sent out an official invite to a mystery press event in Hawthorne, Calif. on Thursday night, promising to provide a "missing piece" — and teasing an image of a white four-sided pyramid-like gadget

The image is clearly modeled on Apple's press event invites — which tend to provide some clue to the product being unveiled. This one might seem more mysterious — if we didn't already have a number of reports that suggest Tesla's "missing piece" is a home battery, similar to a Tesla electric car battery, that can store solar panel energy and provide power if the grid goes down