Lately I started using three new products LinkedIn, iGoogle and del.icio.us
Linkedin is a contacts management tool. It helped me in keeping (and in fact re-establishing lost contacts) with my old colleagues and classmates.
iGoogle is kind of dashboard where you can choose verity of tools of your interest. A lot tools availabe as well like ToDo list, expense management tool, etc.
Del.icio.us is a social bookmarking tool - you can keep you bookmarks here rather than (or along with) browser bookmarks.
iGoogle and del.icio.us are especially useful for people like me who use separate machines at office and home.