Keep in mind that compression is limited by the PDF standards. To get more I do the usual drop in DPI as well as ZIP it later to a zip file.
Titles I use.
DoPDF
CutePDF
PDF995
Bob
I need an image-based PDF printer that has deep compression options. I currently use Zan Image Printer, but it has limited compression options. (Otherwise, it is very good and compresses well.)
Any recommendations you have are appreciated!

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic