Mike and I were discussing ways to translate multiple-finger motions into simple matrix transformations for multi-touch over dinner; a busy afternoon later and he’s produced a great example that makes it look easy. This certainly won’t appear new to followers of multi-touch interaction design, but it’s the first time I’ve seen the code both released and explained in detail. I’ll be porting this to our WPF framework over the next few weeks and will be sure to share my results on the big screen. Thanks, Mike!