How to: Plugins for User Submissions, Post Rating, Most Popular List and Login.

I’m trying to launch a specialized blog, The Little Cheat Sheet, and need to know if plugin exist to fill the following needs:

1) User Submissions: On the Submit a Cheat page, I’d like registered users to be able to contribute their own material. As the administrator, I’d be able to review and revise it and then post it to the site under the contributor’s name.

2) Post Ratings: Next to every post would an icon that would allow any visitor to recommend the post. (There wouldn’t be the ability for a visitor to give the post a negative vote.)

3) Most Popular: In the sidebar would be a list of the most popular posts according to the post rating above.

4) Login/Register Pane: Is there a plugin that puts the ability to login or register in the sidebar. Once the user has logged in, it would show a standard message like, “Welcome, User Name.”