While working on an anthology this week, I discovered the site Free Speculative Fiction Online, an index of sf available to read online for free. All of the links I followed went to legitimate sites where the author had agreed to online publication, so this is not a list of pirate sites. Some of the links are old, for example links to OmniOnline. I had pretty good luck with the WayBack Machine prizing out texts from web sites and pages that were gone.