During a great discussion with Colas in Mandelieu, I agreed with him on this point : our preferred feature in Mozilla (Semonkey or Firefox), the feature that no other browser has, the feature we are now so used to we cannot make without any longer, that remarkable feature is "Find as you type". It's a new way of finding information in a page (although crazy people like Colas and I have been using that for years and years in non-browsing tools), finding it fast, without bloated UI; it's intuitive and easy to use. "Find as you type" is THE feature I can't imagine a modern browser without.

What about you ?