There are a number of exciting instant messenger clients now available to compete for your time and attention. Odigo is one that stands out primarily for its cool look, straightforward approach, and aggressive stance on interoperability with other instant messengers. If you're looking for an IM that offers more than just a basic interface and the standard fare of features, Odigo's bound to please.
Pros: Freeware, strong feature-set and interoperability with ICQ and Yahoo Messenger
Cons: Interoperability with AIM is iffy, must first register with an Odigo server
