I'd really appreciate a bit of help.

The webpage I have at the moment is a bit like a profile page which contains three pictures in the kind of format as shown below (apologies for the hasty PS skills!)

What' I'd really like to do is have the two smaller images clickable ... so that when a user clicks on Pic2 for example, it will swap with the main pic so that it can be seen better.

I think that this should be a fairly simple function. The problem I'm having is that the function will need to be dynamic as it could be any one of the three pictures that are currently in the main position. So how would it be written so that the function checks which picture is currently in the main position and then swaps it with the image that the user has clicked on.

Does that make any sense at all?

Thanks so much in advance for your help ...