The core of how people first learn to do stuff — programming, music, writing, etc. — is to imitate others. It's one of the best ways to learn. Apparently a bunch of students using MIT's educational Scratch programming language understand this. But not everyone else does. NAMCO Bandai sent a takedown notice to MIT because some kids had recreated Pac-man with Scratch. The NAMCO letter is pretty condescending as well, noting that it understands the educational purpose of Scratch, but 'part of their education should include concern for the intellectual property of others.