Icons to Filter Posts by Type

I'm working on a redesign for my website which will use a grid to display 9 recent posts of various types including portfolio items, regular posts, images, videos, etc as well as imported dribbble shots and forrst posts. This lower left grid square will give the reader the ability to filter which posts how in the 9 post slots according to type, and also go backwards and forwards to view more. The plan is to use ajax to accomplish this functionality.