ASPMultiChat
A real-time component-based chat for IIS (ASP) which requires no client-side Java-applets, Plug-ins or ActiveX. [Commercial]

ASP Chat Room
Offers a basic floating-window chat room application. Makes use of frames, cookies, and meta refresh. [Free]

RealAssistant
Live customer support through text based chat. [Commercial]

ZBit Chat
A chat with no page refreshes. The chat is completely ASP and JavaScript based. There are no hidden java applets, frames or layers. [Commercial]

ASP Chat Script
Allows to offer the ability to chat in realtime to each visitor to website. [Open source]

Video Chat In Flash
Live text audio video chat in flash for one to one help desk or community chat board. [Commercial]

Alivesites Chat 2.0
Easily allow users to chat; includes multiple user chats, multiple rooms, listing of users in room, smileys; automatically block out innapropriate names. [Commercial]

ASP chat room
Simple chat: database-less, runs on IIS and PWS. [Commercial]

CuteChat
A full-featured ASP.NET chat application.