It seems that every search engine sooner or later publishes a browser toolbar to bundle all its fancy features--search, news, pop-up blockers, and e-mail--into one convenient, very in-your-face, package. Yahoo takes it one step further by making you part of its gang, too; to fully use the toolbar's tricks, you must register with Yahoo.com. The interface is standard--you can add or remove buttons that launch the various Yahoo services, though we found it a bit inconvenient that we had to "refresh" the toolbar each time to see changes. During testing, we found that the toolbar doesn't slow down normal surfing. The pop-up blocker eliminated most of the ads we encountered, but not 100 percent. Also, if you've had enough, the Companion Toolbar uninstalls without any problems. Overall, this toolbar will become one of your favorite tools if you're a devoted Yahoo fan and want all your toys at a button click.