I think such publication is very important. I have no idea at all if open source search engines could ever work.

But if they can, I think a big part of it would be separation of the crawl index and the UI / prioritisation etc. Different people can work on those two ends of the problem and apply different philosophies.

Search only forums? Reject porn using XYZ method? Great! But they can all use the same database, or pick from the a common community of databases.

That's great news, thanks for the info. Sorry for sounding harsh, for being a side project this is impressive.

Have you also published the ranking mechanism? That way people might contribute you to improve it.

It would be great if you can share (at least) some information about the kind of hosting setup you're using, how much of bandwidth and how long it took to crawl and index the 2B pages.

Thank you for your work. Keep going on it.

Wired you a small donation as I think it is important to have alternatives.