We did do something which sounds similar, at a company I was at awhile back. Effectively, we were just getting rolling with AWS, so Amazon sent some folks in for a one-day intro to some of the different AWS technologies, and the rest of the week was a hack-a-thon of sorts, designed to become familiar with those technologies. That was probably the better of all of the hack-a-thons I’ve experienced, since at least there was an end goal behind it.