Surreal ToDo is an AJAX enabled web 2.0 list manager written in php with jquery and mysql. Lists are organized in tabs that allow multiple pages per tab. Everything is drag and drop for organization.
AnotherTodoList is a little web 2.0 todo list and / or post-it application.
Its goal is to be very user-friendly and easy to use (including drag and drop for items, simple edition by double click, etc).
Monket is an Ajax enabled online calendar. Drag and drop events to change dates, drag the start/end of an event to create multi-day events, create and edit events without refreshing the page, all with an iCal style interface.