One of the problems I have had in my normal workflow is getting lists & ToDoLists on to my PPC. And quite a few of the lists are just simple things like shopping lists.
I use TDL2 on my desktop, but it is overkill for simple things and doesn't transfer easily to the PPC.
I have GemX Do-Organiser which I now use a lot; it's supposed to work with a PPC but I've never succeeded with it (knew that before I bought it, so haven't been disappointed).
I've tried a very high proportion of what is out there without feeling it was successful. I really liked MLO and it always synced very well, but have never convinced myself that I would actually use it much; always felt rather long-winded in use and fairly rigid.
I saw ListPro coming up a week ago and thought I'd give it a try (not sure why I hadn't before). Very configurable/simple or complex. Can set it up for GTD system if wanted - but also any others. Syncs very well. I think it solves this problem.
Also has lots of Lists available for download from website. So it can be used as a way of managing short simple databases too.
Offer is $9.95 for the Windows version. Adding the PPC or Palm versions adds another $10. This offer doesn't seem to offer the same discount on the combined Windows/PPC version (which would have given a price of approx $15). 30 day moneyback guarantee.
If I'd been using it for a lot longer than I have, I think I'd be recommending it.