Look to this content. It is a node concerning Claude Monet with a block wit all the other painters on the site. In the block, Claude Monet is not visible. If you do this with Picassa, Picasso would not show up in the block. You don't have to link to content you're viewing...
How do you do that? You need a contextual filter. These filters are in the URL even if you don't see it.
I first make a view for the all the painters.
Then i configure a contextual filter. I choose the ID.
Important. Below you see Exclude!!!