Ask Slashdot: How Will You Update Your Technical Skills Inventory This Summer?

Proudrooster writes "As technologists, developers, and programmers it is essential to keep moving forward as technology advances so that we do not find ourselves pigeonholed, irrelevant, or worse, unemployed. If you had to choose a new technology skill to add to your personal inventory this summer, what would it be and why? Also, where would you look for the best online training (iTunesU, Lynda.com)? The technologies that immediately jump out as useful to me are HTML5, XCODE, and AJAX. How about...