More accurately, I’m a light Springpad user -now-. I’ve more than put the service through its paces. I think that the GTD implementation for Springpad that I put forward should still work — but I need to do a clean look at it before I can say that with confidence. How do you do your GTD in Springpad? Is it related to the the method in my past article?
As for what I use now, my focus is on Producteev. The interface has been updated since my GTD in Producteev post, but it still works well for me — though it will be better once they recover the features -they- lost or disabled when they did -their- update… Seems to be a lot of that going around lately, eh?
Another viable option is Wunderlist or Winderkit. Both are free, functional, and easy on the eyes — but no attachments, I believe. You may also wish to take a look at my GTD in Evernote post, or take a look at the GTD category in the top menu, here. There are several posts, some of them by us, and some by readers.
There may not really be an all inclusive “one stop shop” out there — not without tweaking or making allowances in some way. Mostly, I focus on free options, however. There are some very good paid GTD-focused services like Nirvana, Nozbe, etc.
Hope that helps!