I recently purchased a Zitelli bag from ebags.com. It's 20X10X6 or so and holds my BOB gear with ease. (specs on the web page are incorrect) It's MOLLE compatible, has plenty of pockets inside and out and has both chest and waist straps. It was $30. If you go to their site and search on "MOLLE" it should pop-up.

Andy

PS, here's the link:
http://www.ebags.com/zitteli/z1_molle_pack/product_detail/index.cfm?modelid=87867
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