@farmerman,
Many years ago during an A2K discussion with Satt_fs I discovered that the basic 7-year solar cycle is due to the sun passing back and forth through the barycenter of the solar system.
As it turns out, this was a known fact long before it came up in our discussion, but it was very fun arriving at the same conclusions from searching information on the Internet, rather than simply having someone tell us. We actually deduced this from our questions to each other, and after coming to our own conclusions we were then able to search out relevant information to confirm our ideas.