I tried the Spongecell calendar and it seemed like it could be a useful tool, but I'm such digital immigrant that I have a hard time considering ever giving up a paper calendar. Maybe someday. The same goes for the list-making sites. What's wrong with a post-it note stuck to the paper calendar? Sometimes I'm away from the computer (it's hard to believe that anyone could walk away) and I still need to remember what I'm supposed to be doing.
Backpack, on the other hand, looked really handy. I can see a situation like this: Another Knowledge Nomad and I are working together yet separately on a project for a client. That would be the perfect repository for our research and information as we're moving along. It could also be a nice way to present final results to the client.
All in all, I think I need to spend a lot more time with some productivity tools to find those that will really change my life. The irony is that I need extra time to do that.