I have come up with a take on free will that is probably not original in the sense of being totally new, but which I have arrived at on my own. To discuss it coherently will require a bit of preparatory material; see what you think.
YOU ARE WHAT YOU WANT
I made the mistake of typing that in a chat discussion once, to be answered with, "Then I'm Salma Hayek". Hmph. Philistine.
To explain what I mean by YAWYW, let me point out that there is a distinction made in our culture between "Wants" and "Needs", and that, in the popular view, "Needs" are more pressing, more primal, than mere "Wants". "I want to go out for ice cream, but I need to finish this assignment." "I want to buy a Mercedes, but I need the money to feed my family."
Do what you need to do first, then, if you have the time, you can do what you want to do. But is this hierarchy valid? I say it is exactly backwards.
Ask someone why they need something, and the answer will be, "I need it to [obtain something that I want]." We are all subject to a wide range of stimuli, and at some level, we decide which ones are the most important, and respond to them, leaving others unattended to. It is merely a wistful childish wish to be able to have everything that leads to the "I want to... but I can't, because I need to..." formula. In reality, you want to finish your assignment more than you want to go out for ice cream; you want to feed your family more than you want to buy that Mercedes. Otherwise, you would be eating ice cream in your new car. Wants are primal; needs are ALWAYS conditional.
So this is what I mean by "You Are What You Want." At the most basic level, it is your desires that motivate you, and nothing else. To change what you want is, in a real sense, to change who you are. In order to change who you are, you must change what you want. The two things are identical. (This is what makes breaking addictive behavior so challenging; the addict must become a different person.)
I started thinking about all this when someone who felt (not without some justification) that I had betrayed and offended him asked me if I knew the meaning of sacrifice. I thought about it for several minutes and came to the conclusion that a sacrifice is just the act of relinquishing something that you want very much for something else that you want even more. So someone "making a sacrifice" ought not to feel put upon, except by the fact that some things are mutually exclusive.
NOBODY EVER DID ANYTHING THEY DIDN'T WANT TO DO
This statement is usually met by howls of indignation, but I'll stand by it. Consider: every time you make a choice, you look at all the options that you can see, and you choose the best one. Every time. Now the definition of "the best one" is a highly idiosyncratic one. Two people faced with identical options will often choose differently. The same person encountering the same choice at a different time may very well choose differently than the previous time. None of the options that are percieved may be appealing; on a scale from 1 to 10, with 1 being "Revoltingly Disgusting/Excruciatingly Painful" and 10 being "Blissfully Ecstatic/Hugely Profitable", all the options you can see may cluster beween 1 and 1.5, but you will still choose the one closest to 10. That is the one you want. This is purely subjective, of course. The only options that count are the ones the chooser is aware of. That an observer may see another option the chooser would choose if aware of it is completely irrelevant if the chooser is not aware of it.
Oh, yes, I did mention this a while ago, didn't I?
I do believe in free will, for the entirely subjective reason that to believe otherwise is repugnant. But it occurred to me that if we always choose the best option that we are aware of, isn't that in some way deterministic? I mean, is it possible to choose an option that is not "the best thing I can think of, at the time, under the circumstances"? I don't think it is, because if I were to make a less than optimum choice, it would be to prove that I can, which would then be the thing that I want, which would make it the best choice...
To state it bluntly then, I believe that, in a world with only one conscious being, that being's life would be completely deterministic. Every choice could be plotted out in advance, if some non-interfering observer could be privy to the being's mental states.
BIOLOGY TO THE RESCUE!
Fortunately, we live in a world of billions of conscious entities (I say, straight-arming Solipsism into a ditch). I am not a molecular biologist, so perhaps I am wrong or mis-informed, but I believe that sexual reproduction combines genes in a truly random way, creating unique individuals whose lives impinge on other individuals, causing them to see options previously unavailable, constantly changing the external conditions that influence our choice of "the best", and preventing this from being a clockwork world. (whew!)