Over the years I've alternated between pencil and paper and electronic diaries and 'to-do' systems. For the last few years I've adopted the bullet journal approach, a very expensive A5 journal notebook and hundreds of HB pencils. And I love it! I'm not artistic, which many bullet journallers are, but for me it works. Those who know me refer to 'the little black book' :). There's no list in there 'come the revolution' though! - iPhone light, ISO 4,000.