Geist List is a day-by-day to do list. It is heavily influenced by Ryder Carroll's Bullet Journal method. It is currently in beta, which is to say it's pretty rough around the edges still.
In Geist List, each day has its own empty list. You can move undone things from previous days to today if you want to, but they aren't moved automatically, and there are other options for dealing with them. You can mark them done on the day where they already are, even if that day is over. And if you decide not to do something after all, you can mark it cancelled to cross it out.
Currently, Geist List has your browser store all your task data. This means you don't need an account! But it also means that you can't sync multiple devices, and there's no good way to back up your data. These things will change as Geist List gets more polished.
Geist List has a Twitter account for posting updates and whatnot.
Currently, all your Geist List data is stored in your browser on your computer, and there are no tracking codes on Geist List. We do keep pretty standard web server logs, which include the IP address and browser info (User Agent string) of everyone who visits Geist List, but we don't have any way to connect that to actual people. So our current privacy policy is simply that we don't collect any personally identifying information.