Ext. Link: Check rowdii.com for websites
“Rowdii adds a forum next to every website in the world, so you can discuss different products, services or web content as well as share files… Rowdii is the only web tool that allows users to link websites together, so you can easily discover interesting sites related to the one you are viewing.”
Ext.Link: librarything.com for books
Brief Biographies: needs to be edited and sorted
Some Notes on Maxwell's equations