David Sparks is one of the busiest guys I know and I'm honored to be able to call him a friend. David along with Mad Scientist Brett Terpstra have produced an amazing new MacSparky Field Guide, 60 Mountain Lion Tips. This book is packed full of geeky tips and tricks to make you more efficient on your Mac running 10.8 Mountain Lion and includes more than 50 screencasts and 1.5 hours of video.
The book is best viewed in it's native iBooks version for iPad and available for download in iTunes. However, if you don't have an iPad, there's a PDF version available as well. You can find more information available at 60tips.com.
Congratulations David and Brett!