Does anyone have experience with loading the vBulletin tables into memory tables?
It seems this may speed up the forum 3000x
in practice according to MySQL performance blog.
http://www.mysqlperformanceblog.com/...vs+bdb+vs+heap
The only thing you would need is a backup system (memory is erased on server restart) and enough ram for the tables.
I am able to configure a varchar field up to 21k chars for MEMORY tables in PHPMyAdmin, which should be enough for most forums I think.