Software by Simkl:

Simkl Tray gives you easy access to Simkl IM History Viewer from your PC. Simkl allows you to consolidate all your IMs - ICQ, AIM, Yahoo, or MSN. It's a Web application that collects all your instant messaging conversations on their servers into one convenient, searchable archive which can be accessed online from any computer. It is possible to generate history for chosen contacts only, search for the newest conversations...