Judging by the start date of this thread, I've been using a paper system for 5 months and it simply isn't working as well as my old electronic system. Don't get me wrong, there are things I like about my paper system but there were more things I liked about my electronic one.
I'm going to temporarily move my stuff back onto Toodledo. I say temporarily because it wasn't ideal either. Part of the problem with electronic list systems is that they is that they are more restrictive than paper. They always want to display stuff in rigid lists or tables. Printing formats often seem like they are thrown in as an afterthought and the interface for editing the relationships between items can feel clunky at times.
I think I can do better. Someone on here said one of the best systems they have used is a relational database. It certainly must be the ultimate in flexibility! I've thought about this and have come up with a simple schema that captures what I want out of a GTD system.
I also have plenty of ideas for a user interface that shows useful views of the data depending on whether you are collecting, processing, doing, etc. I also have an idea that may solve the problem of linking a project to an action. If it works as well as I hope it will, navigating between views will feel incredibly smooth.
I know this project could potentially suck up a lot of time but I work as a freelance software developer and always let myself have one personal project on the go.