Store and merge your Firefox bookmarks.
Google Browser Sync for Firefox is an extension that continuously synchronizes your browser settings – including bookmarks, history, persistent cookies, and saved passwords – across your computers. It also allows you to restore open tabs and windows across different machines and browser sessions.
Google Browser Sync is multi-platform and works with Windows 98/NT/2000/XP, Mac OS X and Linux. You will link to the Google download page.