Responsive Gridfolio
The Responsive Gridfolio has a fluid / flexible / responsive layout. Basically the grid is added into a HTML page into a div of your choice and it's adapting based on that div's width, the grid's height is modified based on the thumbnails and if other elements are below the grid's div they will be pushed down automatically (document flow). In the examples provided you can see a few ways in which you may use this grid and of course that other configurations are possible (please note that the code of this examples is provided in the download files).