ICQ Lite is a no-frills version of ICQ that can be installed quickly and easily, using minimal system resources. You can switch between ICQ Lite and the full version ICQ 2002a from the main menu. ICQ Lite has all the essential features of the full version of ICQ. You can message people, exchange files, send SMS, and meet people. It also includes multilingual support, the ability to save your chat histories, and a typing indicator that shows when a contact is typing you a message.
More info:
hxxp://www.icq.com/download/