Gravity. What goes up will eventually come down unless it is pushed up again. If a satellite is beyond its lifespan, or the station is no longer feasible to maintain—whether the cost is too great, or there are no more experiments—it has to come down. Keeping it up costs resources—fuel.

Nearly all of the courses at edX are free.

Sergey, Larry, and Eric own most of the voting shares of Google. Most of the shares floating on the market either have few votes or none at all.

Elon Musk owns about 23% of Tesla stock (http://business.time.com/2014/02/26/elon-musk-1-1-billion-tesla-tuesday/) and the board of directors probably owns another significant stake. The rest of the shareholders, myself included, don't have much of a voice. Honestly, I am fine with this. I don't know anything about running a car company or building electric vehicles, and I doubt the company leadership would do anything to lose their own money. Tesla is one of the few companies I trust because their motives have always seemed altruistic (aside from the obvious capitalistic qualities of any corporation).

He was not an MIT student or affiliated with MIT in any capacity. MIT has no obligation to protect a physical and electronic trespasser.

"MITian"? We are Engineers.

Yes: http://libraries.mit.edu/sites/scholarly/mit-open-access/open-access-at-mit/mit-open-access-policy/mit-faculty-open-access-policy-faq/

You forgot this.