I have two. My Yahoo email is for my official correspondence and for daily use. The other one is a Gmail account I use for backup in case I forget the password for my main account, and which I also use for signing up for forums and other stuff.
i have two which are both active, i check them both daily and use them both for different things, one for msn and other things like myspace and bebo. then use my other one for such things as buying off the interet