I am a sucker for text editors and in a similar vein, I am a sucker for task managers. I can't help myself from trying them out.
My current setup is using the web-based Remember The Milk sort-of combined with a Getting Things Done methodology. (Oh, and since you ask, I really like Sublime, Vim, Notepad++ and Geany ;)
I did look at using Vim with Vim Outliner for implementing GTD but I find Vim a bit of a headful, although I am persevering.
Wunderlist looks kind of interesting but I'll need a lot to persuade me to move wholesale from Remember The Milk.
Taskwarrior Solarized theme by Stefan Keel
And then today I saw Taskwarrior "a command-line todo list manager". Wow, that appeals to my inner geek. It is available as a binary for most flavours of Linux, there's a graphical front-end, it's easy to use but with lots of extra oomph. And you can set it up to use Getting Things Done (amongst other methodologies).
The only downside is that there doesn't appear to be an Android client available yet, although it does have push/pull/merge functionality (see man task-sync).
Definitely one to keep an eye on.