1) A clone of SEO Friendly Images (I only tried this one because I couldn't get the original to work)
2) Doesn't work (same as the original)
3) No support whatsoever. Many comments saying "doesn't work" both here and on the official site, from months and months ago, with absolutely no response from the developer.
Plugins like this have a negative impact, since they waste time. We'd be better off if it didn't exist at all.