Take online notes.
Crocodoc - A site to share and review documents and presentations with others. Upload a PDF, document or presentation, and users can view and mark them up online. Files can be password protected and encrypted for maximum security.
Evernote - One of the best productivity tools on the Internet! Use Evernote to save everything: notes, pictures, websites, etc. Access them on any device. Free account provides a limited amount of uploads per month, enough to use it regularly.
Lino - A free service that uses virtual sticky notes to take notes and share ideas, or use as a reminder service of important deadlines.
ListThings - "Super fast, free and ridiculously easy" webtool for taking notes. Share and collaborate with others. Access notes from any device.
MySchoolNotebook - Take notes on or offline! This free account is great for students: take notes and access them on mobile devices, share notebooks, add drawings, print and export! Requires Facebook account to register.
Notes.io - Fast, easy, short way to take online notes and share them with others.
Notezz - A free, simple, notetaking tool that is fast and easy to set up.
Quicklyst - Take beautiful, outline style notes on any device with this free web-based tool.
Spaaze - A customizable virtual desktop to collect your links, notes and screenshots.
WriteBoard - Shareable, web-based text documents that let you save every edit, roll back to any version, and easily compare the changes. Docs can also be password-protected.