I have seen some popular websites display their links ending with .html -- does this help with SEO? I assume this can be done via some mod rewrite.
You will find a great mod rewrite how to here : http://forums.digitalpoint.com/forumdisplay.php?f=49 Yes, it does help for SERP.
You can use mod_rewrite or a Forcetype. Although personally i havent seen any benefit in .html (but thats not to say there isnt any)