How about adding an icon to your favorite toolbar?
If that's ok...
Tools|Customize (just to see that dialog)
Now select Edit|Clear (on the toolbar)
And ctrl-click (that's important!) and drag the All icon to your favorite
toolbar.
If you ctrl-click (you'll see a box with a + near it), you'll be copying the All
Icon.
If you just drag, then you'll be moving it!
Now rightclick on that All icon on your favorite toolbar.
Change the Name to something you like: Clear All
And close that customize dialog box.