How do you get that little Yahoo Mailbox icon on your toolbar?

My computer recently reboot itself, and in doing so, wiped my entire hard drive against my will, because, you know, why not ruin my whole week, right? So anyway after getting the thing working again, I noticed that my toolbar no longer has the little Yahoo mailbox icon that it had before the crash. I liked that icon. It made it easy to check my email without having to change websites. So I'm wondering how to get it back, and do I have to install the entire Yahoo toolbar to do so? Because the one little icon is all I really need. It's how I quickly hear the answers to my previous Yahoo Answers questions. Truth be told, after I post this question, I'm gonna go to another website and not even know if someone answers this question because I don't have the icon to tell me. Sigh...