Ask HN: New Year Project suggestions

I'm looking for project suggestions for the new year, something spanning 1-3 months. This is what I'm considering, any suggestions would be appreciated: 1. Automated Stock Trading algorithms (Quantopian or other) 2. Arduino / Pi project (suggestions welcome) 3. Website/app: dating, music, photos, social, finance, etc. Suggestions welcome. 4. Data Analytics project using Machine Learning against a public data source (Astronomy, City Data, etc.) Please share any experiences with such projects. Thanks!