I use the Firefox Bookmarks Toolbar around the clock. Adding new client sites to the toolbar saves me a lot of time for instance. And with Firefox you can simply drag the url in the address box to the Bookmarks Toolbar and you're good to go with a ready site link.
I've been running out of space on the toolbar lately. It dawned on me that I only needed to see the favicons in the toolbar, not the site names, so I tested to see if I could blank-out the site name in the bookmark properties.
Shazam. I could, so I blanked-out all of them with the end result being an icon-only bookmarks toolbar shown below. I don't honestly know if you can get 4 times as many sites on the toolbar with this technique, but it's a lot.
I know what you want to know. Can you do this in IE7? The answer is "no." Site name is required in IE.