timlinden

Remembering to post every day, and which days you already posted, is super easy with this plugin. 
It shows you a calendar with days red when there isn’t a post, and days green when there is. Green 
days you can hover over and see the title of the post, and click to edit the post for that day.

wpFutureCal

A simple calendar that displays when you edit posts, showing which days you have posted on.

msudvarg

The ‘Future’ plugin allows posts with future scheduled dates to be integrated into a site. This can be useful, for example, with events that have associated dates in the future. Such future posts can, with this plugin, be displayed, both individually and in archive lists. This plugin also adds functionality to the built-in calendar widget. It adds a checkbox to include future posts in the calendar, and it allows the calendar to be configured to show posts from a single category.

Future

Integrates future-dated posts into your blog. Adds future posts and category selection to Wordpress's built-in calendar widget.

wpFutureCal vs Future