Safari user, sometime StumbleUpon user. Don’t like having to remember to use Firefox to favorite a site in StumbleUpon. StumbleUpon has a WebToolbar but for some reason does not provide instructions for setting up a Bookmarks Bar button to it ala Delicious.
In Safari make a new bookmark in your Bookmarks Bar called “StumbleUpon” with the following address:
It opens the page you are currently on within the StumbleUpon web toolbar so you can thumbs up or thumbs down it.