A great resource for advanced students containing a wide range of helpful items, including explanations of grammar for ESL learners, tips on writing research papers and using proper citation, and links to many useful writing resources of all sorts.
Online personal journal for computer and mobile phone securely saves and dates writing and allows users to share their entries with others. Students can upload photos or images to enhance their journals, and feedback can be given by others (anonymously if they wish).
This site gives one writing prompt per day. You can write on Plinky's site or your own. You can also see others' responses to the prompt and give feedback.