My website usually have 3-4 times per weeks 1 hour with 10 times more users than any other hour of the week. Assume that the website has 1.000 users per hour but four times per week at 21:00 it has 10000 users online. The website need a server to hold always the maximum (10.000 users), but it doesn't generate the maximum in money (I mean that obviously it doesn't generate the revenues of a website that has 10.000 users per hour, cause it has usually 1.000 users per hour).

The majority of the users in my forum doesn't post and they only read the forum, so I thought that a solution could be a forum in cache in the critical times.

I read something about php-cache but I believe that it doesn't work with a forum. So a solution will be save the entire forum (or at least the last pages of each forum) in static html. Do you know if the mod "phpBB Search Engine Indexer" do that? Or do you know about any soft which makes that with any website?

Thanks in advance