A lot of us intially entered the computer field to do something like program our spaceships' guns and shields, so this rings an important string inside us. Also

A lot of us intially entered the computer field to do something like program our spaceships' guns and shields, so this rings an important string inside us. Also, the CPU is so simple that everything around it (the spec, various emulators, assemblers and compilers) is quite accessible even to people who have little experience with this low-level stuff. In short, if the DCPU-16 and related technology do not fit the "fun hacking" label, then I don't know what does.