Foxmarks: Bookmark Synchronization Heaven

Long have I searched for the magic bullet solution to my bookmark synchronization woes. I’ve wanted a simple plugin that would synchronize my bookmarks between multiple installations of Firefox and Safari, thus making it simple to access said bookmarks from any computer, or between the two commonly used browsers on my Mac. I’ve looked at many options, but always the solution only allows me to sync one browser or the other, leaving me looking for some secondary sync tool to get between Firefox and Safari on my Mac itself, not via network or a proper sync.