Home Page: http://www.mozilla.org/projects/rt-messaging/chatzilla
A basic IRC client that is fully cross platform and written entirely in JavaScript and XUL. You must be using a Mozilla-based browser to run ChatZilla. Originally a proof-of-concept chat device for Mozilla, it has continued to grow and develop, becoming a very useful and portable, albeit limited, IRC implementation. Mozilla still intends to produce a multi-network, all-inclusive instant messaging/chat tool like GAIM.
It now does support DCC file sending (see ChatZilla FAQ)
TakeDown.NET -> “ChatZilla”