How do you avoid getting Zuckerberg-ed?

The best way to avoid it is to make yourself valuable enough that the technical lead can start the company more easily with you than without you. There's a lot of non-technical tasks that are needed in a startup: everything from talking to customers to negotiating contracts to finding investors to drawing logos to ordering pizza. Make yourself really good at those and your technical lead will want to work with you. Don't, and why should they?

Other people can chime in on the legal aspects, but I suspect there's not a whole lot you can do. Ideas are only protectable to the extent that you can patent them, which costs money and gives you only a very limited monopoly. If all you have is a general idea for "I'm going to enter this market," you haven't actually added any value.

That's a false argument: If Zuck was really just a "code monkey who got lucky" he could never have built that business up into anything. The problem with your premise is that it assumes that a site or a company is "one great idea" — that's the case to a degree but it's really "one great idea + execution + the right team to grow it".

Honestly Facebook was far from the first social website — in fact during the web 1.0 era theglobe.com went public and once upon a time there was a great site called SixDegrees.com which lasted from '97 until 2001 and used the same formula that facebook did. But the difference was execution, execution and execution.

On a side note techies get screwed over by business people more than the other way around. For every Gates there are dozens of inventors who lost out on their patents and the like. So your real question should be "How to avoid be Winklevossed?"

Look, to be part of a startup you need to be providing value equal to your equity share. Otherwise you're leeching. If you're non-tech you can add value through getting word out, negotiating, and taking care of all non-tech business issues (legal, accounting, marketing, sales), basically things a tech is usually not very good at.

If you are not valuable equal to your equity share, reduce your equity share to a more appropriate value or GTFO.

I calculate equity split on my startups using an auction format and it just works: http://nerdr.com/hacking-the-50-50-equity-split-using-shak/

How do you avoid anyone from stealing your idea?

Of course there is. The startup should have a good lawyer, which will provide you with the usual employment agreements and IP assignments, customized for your area.

There are three situations:

1) the idea is sufficiently novel that it would be difficult for an average person to conceive without suggestions

2) the idea is commonplace, but the value-add is something that is not obvious

3) the idea is a clone.

In the third case, there's really nothing you can do to protect yourself.

The second case is what happened to the Winklevosses. Their value-add, the idea of exclusivity, is something that a lot of people write off as obvious. However, and a poster correctly pointed out, the idea of social networking is commonplace. The cachet was an idea that the Winklevosses figured out, and that essentially was what propelled the entire project (had that been commonplace, someone else would have tried a long time ago)

Again, its difficult to protect nontechnical people in this circumstance, but the idea would be to let the technical people build the standard stuff first and then reveal the value-add after trust has been established (the winklevosses made the mistake of revealing the value-add way too quickly, before establishing trust)

In the first case, you definitely want to learn the technical stuff yourself. Especially if the idea is really good, in which case any developer would try to zuckerpunch you. You don't really have any protection, other than potentially trying to patent.

Thanks for the advice everyone