I have always wondered about this one. I use "id" with CSS and "name" with forms but is that really why these 2 are separate? What is it about them that they had to be separated?
I think name was introduced by IE browsers, and id is the W3C standard. Usually is a good idea to use both on same element, to achieve cross-browser compatible code. Example: <form name="myform" id="myform">...</form>