Using the googleon/off HTML hints to tell Google not to use parts of the page for its snippet

This morning I was tickled to learn that there are ways to add some fine-granularity control to Google’s page indexing behavior. If you add some hints to your page in the form of HTML comments you can tell Google’s search engine to ignore the text for all purposes, for the search result snippet, and more.

For instance, if you search for “granularity seqmedia” you should come up with a hit to this very post. But the snippet text should not be the first sentence in this post but rather the preceeding sentence. (I’m using the googleoff:snippet hint.)