Windows/Mac/Linux: There are quite a few command line to-do lists out there (like our own Gina Trapani's Todo.txt), but if you want something minimalist that will force you to stop organising yourself and just get to work, t is a good bet.
The main goal of t is to be as minimalist as possible: there are no fancy features, just managing tasks as simply as possible. You can't split them into projects, set priorities, order them, or do anything else. The developer explains the reasoning behind this decision best:
It's easy to say "I'll just organize my todo list a bit" and spend 15 minutes tagging your tasks. In those 15 minutes you probably could have finished a couple of them.
T was inspired by j. It's simple, messy, has almost no features, and is extremely effective at the one thing it does. With t the only way to make your todo list prettier is to finish some damn tasks.
We spend a lot of time focusing on how to organise yourself and how to craft your productivity strategy, and if you're anything like me, you can often get lost in the organisation and forget what your'e actually supposed to be doing. This app fixes that by making your to-do list as simple as possible. It's easy to manage using the command line, and you can also view it as a text file if you need to.
T works in Mac and Linux without much fuss (just save the python script wherever you want and add it to your ~/.bashrc as described on t's homepage), though if you want to use it on Windows you'll need to make sure you've installed Cygwin first. To read more about how t works, be sure to check out its home page — it's a pretty interesting (and refreshing) approach to to-do list management.
T is a free download for all platforms.