Music Hack Day was a 24-hour coding challenge where developers were encouraged to build apps at the intersection of music and technology. The event, held at TokBox HQ, featured a wide range of innovative projects, including online karaoke, tweet-based playlists, and even an app that allows users to control laptops with plug-ins using SMS commands. Some notable Twilio-powered apps included Instrumentio, which connects musicians to share gear, Biscuit Orchestra, which enables laptop orchestras via SMS, and Maebe, a hotline that unlocks new tracks from artists like Beastie Boys and Trent Reznor through a Twilio Hotline. The Bonhamizer app re-imagines any song's drum track in the style of Led Zeppelin drummer John Bonham, offering a unique musical experience.