I am on my third position that "required" a BS, and I don't have one, and I don't have the experience required for "equivalency". There is no real secret to doing this, but there are a couple pointers:
Networking: (not in the computer sense) Who you know is often a wonderful way for Autodidacts to find good jobs that will let them grow. People who know you, or know of you, will often know that you are as good/better that another applicant that has a BS.
Resume: Beef up your resume with actual examples of what you can do. URL's if CGI is your forte, listing technologies with examples of how, and what you have done with them is a great strategy for resume building.
Links to existing code that you think is your better work, I have interviewed and hired/rejected over 150 people so far, and many of the first (pre-interview) conceptions are based on: - do the URL's he/she listed work?, if so is the content worth my time as an interviewer, do the skills on the resume fit what I need in a employee in that position? Much of this is the same if the intervewer has a BS or not, as many of my fellow iterviewers have BS and they look for the same thing.
The key thing to do is use both networking and the resume to try to bypass the HR layer, the HR layer is a nightmare as they filter anyone who does not match the requirements. This can be hard to do, but use friends and contacts to get e-mail addresses of hiring managers or even get friends, or friends of friends to recomend you. (this should not be hard as many firms offer bonuses for successful recruitment)
It can be tough, but keep trying and keep your chin up, your ship will sail!
"Nothing is sure but death and taxes" I say combine the two and its death to all taxes!