1632, the RPG based on the book by Eric Flint of the same title, is available free until the 16th on . Based on the D20 OGL it seems like a nifty setting, I will be stealing some concepts for my homebrew setting, which is based on the same period of history. (The 30 Years War is so bloody depressing... makes a great backdrop for a game!)
And the book itself is also available as a free download from - one of the biggest and best internet marketing gimmicks I have ever seen.
Baen is of the opinion that you won't be satisfied with reading it on your monitor, and will rush out and buy it in book form. Heck, it has worked on me on occassion!
The Auld Grump, who was familiar enough with the period when reading the book that one of the plot twists... wasn't.