I know Chrome's address bar also does searches, but somehow I find it much worse at actually finding what I want. It's perhaps unfair since I use Firefox much more, but I visit some pages regularly in Chrome and I'm 90% sure suddenly it doesn't find these - or they are just ranked way off.

Firefox also find open tabs (so you can jump to the open tab instead of opening a new tab) and allow you to explicitly search for bookmarks, open-tabs etc. The open tab thing is also nicely integrated with Firefox sync (not sure if Chrome has something similar)