Ghost Action GTD gets things done with iSync
As if enough GTD apps aren't already landing (or still in the oven), a new kid has just hit the block in the form of Ghost Action GTD. It takes a more basic GUI approach to getting things done, with the addition of full-featured syncing. Like Actiontastic, Ghost Action GTD syncs with iCal, but it goes one big step further by syncing with anything that plays nicely with iSync, including PDAs and even your iPod.
A 14-day trial can be had from Ghost Park Software, and a license goes for $19.95.