ulfben

Note: This plugin has been superseded by the much improved <a href="https://wordpress.org/extend/plugins/custom-upload-dir/" rel="ugc">Custom Upload Dir</a>.
Daily Upload Dir will:
<ol>
<li>add a daily subdirectory to your upload path</li>
<li>use the current post’s date instead of the current date. (eg: adding files to a post from 2003-03-23 will put the files in <code>/uploads/2003/03/23</code>) 
Copyright (C) 2007 Ulf Benjaminsson (ulf at ulfben dot com).</li>
</ol>
This program is free software; you can redistribute it and/or modify 
it under the terms of the GNU General Public License as published by 
the Free Software Foundation; either version 2 of the License, or 
(at your option) any later version.
This program is distributed in the hope that it will be useful, 
but WITHOUT ANY WARRANTY; without even the implied warranty of 
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 
GNU General Public License for more details.
You should have received a copy of the GNU General Public License 
along with this program; if not, write to the Free Software 
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA

Daily Upload Dir

Organizes your uploads into year, month and day-based folders. Uses the post's timestamp when creating dirs.

Yudhistira Mauris

This plugin helps you create a series of posts. It creates a new taxonomy named ‘series’ (can be modified via filter, see FAQ). There is no setting needed for this plugin. Once it is installed, assign posts you want to group as a series via post editor.
The plugin also creates a posts navigation on posts that belong to a certain series. See screenshots for the examples.

Easy Post Series

Works beautifully and doesn't have a sucking frontend design, as other similar plugins do!

Daily Upload Dir vs Easy Post Series