At last nights meetup there was a lot of people using Renoise to produce music and an equal amount of people that had never heard of it or used it. Below is an introduction video to Renoise and you can also click here to see the main overview on the Renoise website.
Added bonus: Check out this article from Create Digital Music about artist Dkon and an album he did using only a Korg Poly 800 and Renoise.