[scott_s]

Both the ACM and the IEEE allow authors to post the final version on their personal website, or the website of their institution.

Of course, the ACM and IEEE are professional organizations, not for-profit publishers. So they can actually move away from the pay-per-access model and still continue to exist. I don't see how for-profit publishers can.

[Fomite]

One of the problems is the number of professional organizations who use a for-profit publisher for their journal's output.