2) Annotation Tool: Google Docs

I made a few sample google docs, testing the commenting and collaboration features. Anybody with the links can edit them. Feel free to do so:

Document: https://docs.google.com/document/d/1bWqRCKbGGaqDDCg6Kp4eMffP8N-PamFX8g9d8v5pFRQ/edit?usp=sharing

Spreadsheet: https://docs.google.com/spreadsheet/ccc?key=0Ai1iCm72d8xldDZ2S2hZekNUZEltYkRsS01TWGMwY3c&usp=sharing

Presentation: https://docs.google.com/presentation/d/16BaRLpE3FELUZW1Pb-t7hysjWXPjvQJBdZ0HwqUQhrk/edit?usp=sharing

Drawing: https://docs.google.com/drawings/d/1SYZJTM6rlNQPwbTF7pKm2_2tu5ZyIrBUJBK-lyELg0Q/edit?usp=sharing