RewriteEngine On
RewriteBase /
# Discuss rewrite rules
RewriteRule ^forums/thread/([0-9]+)/(.*)$ forums/?action=thread&thread=$1 [L,QSA]
RewriteRule ^forums/u/(.+)$ forums/?action=user&user=$1 [L,QSA]
RewriteRule ^forums/board/([0-9]+)/(.*)$ forums/?action=board&board=$1 [L,QSA]
RewriteRule ^forums/category/([0-9]+)/(.*)$ forums/?category=$1 [L,QSA]
RewriteRule ^forums/(.+)$ forums/?action=$1 [L,QSA]
RewriteRule ^forums/(.+)/$ forums/?action=$1 [L,QSA]
# The Friendly URLs part
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*)$ index.php?q=$1 [L,QSA]
This question has been answered by juro. See the first response.
