There's this great new Application called AIM Lite (aka AIM ET) available to download at http://x.aim.com/laim/. Its an extremely small file, and has many features of regular AIM (file transfer, IM logging, Buddy List® management, friendly names, basic custom away messages, auto-hyperlinking, filtering, Offline IMs, themes, plugins, and messenging while away with extremely low memory usage. While it wasn't designed to be so, it can be run from USB. When you download, remember to press Save instead of Run to save it on your USB (this can be deleted after installation and tell the installation program to install in the USB drive, and delete the desktop shortcut and program file folder in Windows to get the full portable experience. Only tested with Windows. Give it a shot!