TDO Mini Forms plugin allows you to add highly customisable forms that work with your Theme to your website that allows non-registered users and/or subscribers (also configurable) to submit posts. The posts are kept in “draft” until an admin can publish them (also configurable).

It can optionally use Akismet to check if submissions are spam. TDO Mini Forms can be used to create “outside-the-box” uses for Wordpress, from Contact Managers, Ad Managers, Collaborate Image Sites, Submit Links, etc.

The plugin provides an extensive moderation view so administrators and editors can see posts awaiting approval and publish or delete them. Administrators can also ban specific users and IPs from using the form. Registered users have access to a “Your Submissions” page which lists their current submissions awaiting approval and links to their approved submissions as well.

Pricing: Free
Requirements: WordPress 2.7+
Source: http://wordpress.org/extend/plugins/tdo-mini-forms/