You can manage multiple Gmail accounts – two or more gmail accounts, either the crude way by opening different account in different browsers or the more sophosticated way by using Gmail Manager Add on for Firefox.
With Gmail Manager you can :
> Login to and logout of, more than one account at a time, within a single browser, which is Firefox, of course.
> Receive new mail notification for all accounts
> All the passwords can be stored
> One click Gmail account access
> Read the labels of all new mails, makes it easy to decide which mail you want to check.
> Compose mails from a specific account