Export to Text by jcskyrock is a very simple plugin to export published WordPress post data into a tab-separated text file format (TSV).
If your goal is to extract all the main post fields (including custom fields) into text with each row representing 1 post, then check this out.
Export your data in an Excel-friendly format
Easily move your posts between WordPress installs when used in-conjunction with CSV Importer ( http://wordpress.org/extend/plugins/csv-importer/ )
Make quick backups of your posts and save them in a text file