Skins
Benzene265's Yahoo! Messenger Skins, j7172's Yahoo Messenger Skins, Leafy Goodness, RaiderMP's Skins, Reap Vengeance Yahoo! Revenge Skins, Scarlett's Yahoo Skinz, Theme Depot - Your Source for Custom Themes, TopDesktop.Com, Tricia's Yahoo! Messenger Skins, Waldoo Skin
Y!TunnelPro
Add-on aiming to protect Messenger users from abusive and malicious chatroom activity. [Requires Windows].
Yahoo Messenger
Allows you to instant message with anyone on the Yahoo server. Tells you when you get mail, and gives stock quotes.