I've been looking everywhere with no luck, so maybe someone here can help me. If you end up having to code it for me, I'll give you credit and put you in my blogroll.
So it's really easy to find a random post widget that just shows a list of links, but that's not what I want. What I want is something that will show only one post at a time with an image and a text exerpt. I also only want it to show posts with the label "favorite products".
If you look at my blog now (http://www.orangeraspberrylemonade.blogspot.com), you'll see that there's a section in the sidebar that shows a favorite product and a link to all the posts with that label, but I have to update it manually and therefore only one post is getting attention at any given time.