Completely FREE to-do list organizer, that allows you to create categories. Absolutely beautiful app that works on pc/mac/iphone/ipad/android

For a more full-featured team-oriented app made by the same people, visit wunderkit.com (or see my review of it).

This is the best To Do list app out there. You can download it for your desktop and for your iPhone/iPad or Android and it syncs automatically.

You can create different lists for errands, tasks, groceries, etc. I was able to set reminders on my iPhone but couldn't do it on the website. You can even print and email your list.

You can even email a task to your list:

Just send it to me@wunderlist.com (you have to send it from the email account your registered with)

Subject: Enter the list name

In the body: list the tasks and put an * next to the ones you want to star.