This bird showed up at my bird feeder last week. I wasn't familiar with it: a Carolina wren. We live at the northernmost reaches of its habitat. When I looked it up in my bird field guide book, I noticed a penciled in comment: 12/24/2007 at suet feeder. So it had been three years since I last saw him.
To Carolina wren: you are most welcome to come more often, but discovering you was such a treat!