Responsive Image Grid

[imicleVet]

I'm trying to design a responsive image grid similar to the new Rdio Web App. example screencast hereThe grid should have the images across the screen at 300px max width (200 max height), but if the user shrinks the window, they would scale down to 200px width (133 height), then have one less column at 300px.I have the grid laid out with left floating and the correct margins, but not sure what to put for max/min width and height.