The official IE blog today has a tantalizing write-up of some of the new code that will be rolled out in IE8 beta 2 - code that will allow just one tab to crash without taking down the whole browser. And that tab, in many cases, can automaticaly recover itself, including related sessions cookies and form data!
Since beta2 is not yet available, we can only anticipate and not yet test this - but it sounds very intelligent and user-friendly. Many IE users may barely be aware of what's going on.
[blogs.msdn.com...]