Update a block from another block I want to write a page that works like this:
http://www.albemarlegallery.com/artists.php

i.e. when I hover over a link from one block, an image in another block updates

How can I do that?

Thanks
You can use javascript and ajax to update your image
just when hover your link replace src of image It is javascript only
it is not drupal all your html in the same page so it is easy to change any block when hover over another block