Peter David has reported that his prose character Sir Apropos of Nothing will be returning in the form of a novelette titled "Sir Apropos of Nothing and the Adventure of the Receding Heir." It will be published in an anthology titled Heroes in Training, edited by Martin H. Greenberg and Jim C. Hines. No release date yet.
As much as I've enjoyed a lot of PAD's comics, with the exception of a lot of his stuff on The Incredible Hulk, there isn't much of his funnybook work that I've enjoyed as much as his first two Sir Apropos of Nothing novels. I've never managed to get my hands on a copy of the third book, Tong Lashing, and apparently the publisher closed shop.