volci

There's also Udacity

I guess that is akin to needing 125 rep on the SE sites to downvote (though voting buttons are visible prior to having the ability to do so)

I think it's more that they all start neutral and can only go up - that is a very different case than being able to drop

Guess I missed that in the FAQ - but it's still a little bizarre. It's a fundamental failing (I think) in the majority of social networks (facebook likes, g+ +1s, twitter RTs, etc) - once something hits a certain level of "popularity", it can't become "unpopular"

You travel a [generally] significantly shorter distance when flying, and at a notably higher rate of speed (though normal cruise speed will likely be lower than max rated)

So a drop in mpg is completely understandable

Also, there is a lot more causing drag (the wings at least) when it is flying vs when it is on the ground

Terrafugia (and others) have been making fantastic technological inroads across industries: good to see the FAA is taking solid note

I start, like tjr, with the ToC. Then I check the index (if it's in my hands). Then skim a few chapters - see if the content under interesting chapter headings is written well and\or usable by me. Lastly, what is the price? Regardless of cost, if it's not one I'll read over and over \ refer-to constantly, I'll go to the library and check it out for a couple weeks, picking-up what I want/need from it