Much like Highrise,Backpack is a tool to help you organize. I’ve been using it over the last week heavily and it has really helped me organize. Email/text reminders created in plain text, as well as lists, notes, pages, and a calendar if you get the paid account. You can share pages with people to gather all the notes and thoughts in one place. I think this is an extremely useful web application and I strongly recommend it. 37signals puts a lot of thought into the design and usability of the apps, and it really shows.

(link to post)Visit Backpack by 37signals