Anyone tried Tiddlywiki & mGSD?
It is web-based and lightweight. It doesn't require lots of tweaking and has all the nuts and bolts of the full GTD workflow.
I've posted a thread about an issue here:
http://talk.maemo.org/showthread.php?t=65779

I do believe it's one of the most essential PIM app for mobile platforms. It has already been ported to N800 but there is no N900 build yet.

... but no one seems to be interested?