Really good read, and great tips on how to run an internal hackathon. 100% agree on having a theme open to interpretation, prize categories, and kinds of prizes you are giving. :)
Are you guys running it quarterly already? How much time have you guys waited in between hackathons? Also, you say "every engineer who was present was expected to participate". Were the other departments allowed/expected to participate as well? This is something really positive for improving internal relations.
(Responding for Jon because he's in meetings this AM) -- The first two questions are related, and actually somewhat adressed in Jon's "frequency" section. I'm not sure what the "exact" distance between the events should be, but as he mentions in the blog post, "setting the events far enough apart that each time feels like a special event - a welcome visit from an absent friend."
This is likely different for different people and companies.
Regarding other departments -- yes! Everyone participated in giving ideas, feedback, etc. In fact, it's actually the sales people who fell in love with the results of the hackathon the most and are now vocally asking for more hackathons.
Are you guys running it quarterly already? How much time have you guys waited in between hackathons? Also, you say "every engineer who was present was expected to participate". Were the other departments allowed/expected to participate as well? This is something really positive for improving internal relations.