- New York (original) http://www.stupidhackathon.com/
- San Francisco http://stupidhackathon.github.io/
- Toronto http://stupidhacktoronto.com/
- Amsterdam http://www.stupidhackathon.wtf/
- Tirol, Austria http://stupidhackathon.at/
- Berlin, Germany http://stupidhackathon.de/
- Sweden https://www.stupidhackathon.se/
- Oslo https://stupidhackath.no/
- Hawaii https://stupidshitnooneinhawaiineedshackathon.github.io/
- Boston https://bostonstupidhackathon.com/
- Cologne http://www.stupidhackcologne.wtf/
- London https://stupidhackathon.uk/
- Shanghai https://stupidhackathonsh.github.io/
- Rhode Island? http://steamwith.us/useless/
- Thailand https://stupidhackth.github.io/
- Singapore https://supersillyhackathon.sg/
Disclaimer: I'm one of the co-organizers of Super Silly Hackathon.
Otaniemi, Finland https://www.facebook.com/events/1897344383828900/ (source)
Toorcamp https://frab.toorcon.net/en/toorcamp2018/public/events/51