So, let me be the one to come out and say this:

I've been in several interviews, both at startups and on more-established teams, where a record of no-traction startup failures was a real neg. It can have the appearance of someone who doesn't want to buckle down and work.

There is no reason --- none at all --- that you should put disfavorable information on your resume. Pick a couple (2) of the most interesting-looking attempts and showcase them. Leave everything else out.

Obviously, subcontracting, consulting, temp, and meaningful volunteer and open-source work should get written up. If you worked for name-brand clients who you're allowed to mention, and you were there for more than a couple months, list them as if they were jobs, with a subhed like "on behalf of XYZ Consulting, Inc.".

If you did most of your self-employed work under a single umbrella company name (and, everyone else, here's a good reason why you should), list that company for the largest possible time span. Freelance work counts! Having helped run a consultancy for 4 years now, I'd look more favorably on someone who managed to keep a freelance practice running for 7 years.

Not sure if this will translate to your situation, but I eventually figured out that resumes need to show I created specific tangible benefits to whomever was my employer at the time. For example, rather than say "Have 5 years of Blub", I'd was better off saying, "Wrote code in Blub that reduced transaction processing time, resulting in greater sales of foo."

Are there things in your experience that demonstrate the ability to add value (even if the overall project failed)?

Brought a product to market? Improved overall development time? Unless you're applying for some grunt cog coder job, I think (or hope, at least) that showing you are capable of producing value under pressure would be of most interest.

Whoever hires you can teach you the stuff you don't know.

I had that same issue come up for me and I think the approach I've taken isn't terrible. I updated my resume and for years I was contracting, I wrote a seven word synopsis for each project I did during that time putting it all under a big heading of "Contracting". I sent my updated resume to some recruiters and they've gotten me several interviews. On the interviews, I've gone into great detail on the relevant projects and mentioned the companies I worked for.

I haven't gotten a job from that part yet but at the same time that I was dealing with recruiters, I called all my best clients and told them what was going on with me to let them know I wasn't going to be available for future work. During that call, I asked them to keep there ears open for anyone who needed me full time. I ended up getting a job from one of my clients with the understanding that I would be looking for a full time position. I had to give him a really low rate though but the dependable income is really nice, especially considering how many times I haven't gotten paid on jobs.

From what I have seen in the recent market in california, if you are a coder you should be ok, if you are not then you need to network a lot. People tend to see big name companies and think they are a lot more worthy than people who have been working on their own startups. I don't agree, but it is what I have run into. It may be different in SF than LA but getting through that first HR person hurdle tends to be tough.

If you are a coder they have no understanding of what you are doing most of the time so they just forward it up the chain more readily.

I had an even more extreme situation: 15 years of self-employed bumming, startups, small-business and I did very little programming.

How I got a full-time programming job:

Find industry that I was interested in.

Research company that I was interested in.

Brush up on industry and company specific domain knowledge.

Tailored my CV to be relevant to company.

Get interview(direct personal e-mail to person responsible for hiring).

Nail linked-list building and recursive tree traversal in the interview.

Show industry specific knowledge in the interview.

Get job.

Note: industry specific knowledge was as important as programming knowledge.

Two extra things you could consider:

1. Think of what you'd like to be doing and accentuate those achievements that reinforce your past success in the areas that will allow you to do more of what you want.

2. In my experience, generalist experience often helps you in tricky situations once you have the job. But, it doesn't win you jobs. Recruiters will gloss over that stuff or even simply reject your CV. Accentuate your strongest skills and achievements that clearly demonstrate them.

In the current job market, you want to position yourself as someone who consistently delivers above average results that can't be off-shored. So all those learning experiences (failed startups) are best papered over.

You do the same thing everybody else does, show them what you have done, and what you can do for them. The fact that you were involved in startups and managed to stay afloat last 7 years is an asset to you, not a liability.