Any suggestions?

actiontastic is pretty good, but it depends on what you want to do

What about an online tool? The ta-da list is awesome and has SMS capabilities...anywhere you are at, you can SMS your tasks to it.

Remember the Milk is working for me, especially after I cornered Omar last week to understand how it all works. I've also used Backpack, but RTM is more focused on to-do lists, so has more features. Not perfect but pretty good. And free.

There is that one that comes with the mac, omnioutliner

I use Backpack a lot, but that's because I have to be away from my computer 

task list - i like backpack.. but if its just a matter of a simple check/task list.. try Check Off - really basic tool

Thanks all. I'm actually trying out ical for now, it's ok but reminders are pretty dumb at times and limited.

ToDoX is good as is Ghost Action.

backpack + widget, works perfectly!

Definitely Kinkless GTD, until OmniFocus comes out anyway

(kGTD requires OmniOutliner Pro)

iGTD for Mac is great now, and getting better all thetime.  And it's free.  I've used Backpack, RTM andVitalist, but just find web apps too unresponsive.

Yeah, I must admit iGTD is very nice, although I've been using remember the milk.

Just remember that to get full usage out of any of the GTD apps, it's pretty much essential to give Getting Things Done a quick read

IGTD is definitly the way to go

OmniFocus is nice...

I'm still using a text file...............

if you are a textfile fan, you might find xPad helpful (and its free!)

check out Midnight Inbox. Goes with the GTD (get things done) concept and has a really beautiful interface and cool features that helps you be more effective. What makes it better than the other ones is it use of GTD and has a great relaxing interface. Still in beta though.

I have also tried Nozbe that is a cool web2.0 approach to GTD and to-do lists but i prefer an application such as Inbox that easily can be synced with ical and my devices.

Ok I am going to change my vote to Things, it is like if OmniFocus was designed by 37signals.

http://www.culturedcode.com/things/

I'm using Things now as well. It's a great program and doesn't seem to be as complicated as OmniFocus

I use things as well now. Found it by chance, like it very much.