Pidgin is an tiny application that allows you to connect with all your friends through most of the chat networks in one place. It supports AIM, MSN, Yahoo, Google Talk, IRC, QQ, Sametime, Zephyr, Bonjour, Groupwise, SILC, XMPP, Gadu-Gadu, ICQ, MySpaceIM, SIMPLE (upphhh - that's a lot), and it can support many more with plugins.
Adium is a free and open source instant messaging application for Mac OS X. Adium allows you to chat with all your friends using different chat services at the same time. Among others, it supports: AOL Instant Messenger, including ICQ and MobileMe, MSN Messenger, Jabber, including Google Talk and LiveJournal, Yahoo! Messenger, including Yahoo! Japan, and Bonjour. It is also compatible with iChat, MySpace IM, Facebook Chat, Gadu-Gadu and more.
"Puppy Linux 2.15CE (Community Edition) is the result of collaboration between a team of Puppy Linux enthusiasts. It is built upon version 2.14, but includes many enhancements. In particular, the guys have worked on an improved user interface and a nice out-of-the-box first impression. They have also developed some SFS files that add OpenOffice.org, web and graphics applications; SFS files are 'combo packs' of applications that can be installed and uninstalled with a few clicks."