"When they're gone"
On the rare occasion that I'm home alone, besides doing a happy dance, I love the quiet time I have with the Lord. I'm working on a great devotional series with a friend. Right now we are working on "Be Faithful" (which covers I & II Timothy, Titus, and Philemon) by Warren Weirsbe. My friend and I do about one lesson each week then report through facebook. We're almost finished with this book, and our next study will be on the book of James. It's nice to do the study and then talk about with a friend. I am always amazed at how we get different things from the same verses.
I also love to read missionary biographies. Although I don't do this exclusively when the kids are gone (which rarely happens, mind you), I do love the quiet time to just sit and read.