AMSN

AMSN is a Microsoft Messenger clone. It allows you to keep in touch with your friends and exchange instant messages and files.

aMSN main features include: Offline Messaging, Voice Clips, Display pictures, Custom emoticons, Multi-language support (around 40 languages currently supported), Webcam support, Sign in to more than one account at once, Full-speed File transfers, Group support, Normal, and animated emoticons with sounds, Chat logs, Timestamping, Event alarms, Conferencing support, Tabbed chat windows.

More features can be added to aMSN with plugins , or completely change its look with different skins.