If I could only have one Firefox add-on, it would SiteBar Client. All the others I could live without. If you have multiple computers and need a common set of bookmarks handily available to all - or even share with others in real time - Sitbar and Sitebar Client is the solution. I've been using it since the first version. The frustrating problem is how frequently Firefox is updated, rendering Sitebar unusable until it is updated. So I do not update Firefox until Sitebar Client is updated. It's that important. Fortunately Sitebar Client for Firefox 4 was working in Firefox 6, but it doesn't work with Firefox 6.02. I'm desperate for a Sitebar Client update. For those who don't know how Sitebar and the Client add-on works, here's a fans description. If you load the Sitebar server on your own PHP enabled website, then you can create a private area for yourself, and any users you create, to store and organize bookmarks. Then with the Sitebar Client add-on, you log into your server and all your bookmarks appear in the sidebar. When you're browsing a site and want to bookmark it, the SiteBar Client lets you right click on the page and save it into any selected folder associated with your SiteBar server login. When you hope on another computer and login to your Sitebar server with the SiteBar Client, the site you book marked on the first computer is there. I use Sitebar and Sitebar Client for my IT support customers. When people get new computers or work from home, we don't have to export/import all their bookmarks. I'm amazed more companies don't use it, and that this is only the second review of the Sitebar Client add-on.