I've been considering this rewrite thing to eliminate sessionhash and add .HTML for google and such to index efficiently, but there are many hacks out there for this purpose.
I'm probably going to go with the one Filburt has posted at vBulletin.com as it requires little hacking, and Fastfowards didn't work too well.
What is your version of this Erwin? Is it a hack that could be released, or is it integrated very deeply into your site that to prepare a hack for it would be too troublesome?
I took a quick browse through your forums Erwin, and you did a great job with the rewrite, and how it's all organized