Well, email... but it's not that Netscape has features that IE doesn't, or vice-versa... I just prefer the menus, button placement, etc. in Netscape. It's all just a matter of what I'm used to... plus, I can use Netscape on Unix platforms such as Solaris.
And you can move the buttons around in IE, put them wherever you like...!
Or you can just use Netscape, if you want!