I just recently discovered the Foxmarks add on for Firefox. It allows you to sync your browser bookmarks between different machines via the web. You install the add on, set up a user name and password, and then upload your bookmarks. From then on you can sync them on the fly. It will even merge the bookmarks from several machines so that you get true syncing between them all.
For someone who uses more than one computer in different locations like I do it's a pretty handy little addition to the Firefox browser.