Here's the reason I do not allow Google Toolbar on my machine (besides I tried it once on a work computer ran into all kinds of stuff): Info from: http://www.greymagic.com/adv/gm001-mc/ "We found multiple security flaws in the Google toolbar; we will first list them all (sorted by severity) and then supply details. Without any user interaction, an attacker can: * Tap to key presses in the toolbar's search box. * Control all visual configuration options. * Enable features with privacy implications. * Clear the toolbar's history. * Completely uninstall the toolbar. * Hijack the toolbar and reroute searches. * Execute arbitrary programs. * Read local files. * Script in the "My Computer" zone."