IFilterShop is at it again...if you need more IFilters for sharepoint, check out these guys...they've just added a chm IFilter and have a bunch others like...
- chm
- wma/wmv
- shtml
- msg
- pdf+
- zip
- vcard
check them out: www.ifiltershop.com
UPDATE: i didn't know about these either, but they showed up in the comment thread so i thought i'd bring them to the surface: http://www.citeknet.com/ (they have some free, fully functional ifilters)