I have one email address I give out for mailing, internet, stores, newsletters, etc and I have another one for family and business related stuff. That way I don't have to sort through 100+ emails everyday.
On another note deleting your account on here does not necessarily mean that everything you posted is deleted, it means they de-activate your userid and login information. If you've got blogs, PM's etc on here you might want to drop a note to the Mod's if you want them to ensure everything is erased.