Users select 2 categories and results display post only belonging to both

Hello everybody,

I’d like to display a list of categories (each with its own image, like a gallery grid) and the visitors should be able to select 1, 2, 3, etc. categories, all at the same time, click the “confirm” button and get results displaying posts ONLY belonging to all the categories selected.

Example:
List of categories:
– small
– red
– round
– square
– blue
– big
– violet

If the visitor selects Red+Round+Small the results should display the post “Tomato” which belongs to exactly all the categories selected (no less, but it can belong to other categories, the important thing is that it belongs to all three selected), but NOT “chilli pepper” which does not belong to the category Round.

Is it possible? Is there a plugin (or hack) to do that?

Thank you so much!

Elena

website: http://www.fanheart3.com/