For daily tasks, if I have a lot of little things to get done, I find it satisfying to print out my txt document of tasks and bump them off the list with a sharpie. Feels good, man. For my own long term stuff, I used to use Google Wave, but they killed that, and I lost a pile of ideas Now Google keep, which is nice to create lists, and delete stuff from it. For professional stuff, I've used Jira, Basecamp and Trello. I like Jira's nesting, but I prefer Trello's collaborative organization, I just wish things were nested.