TIEro

This plugin is now available as part of <a href="https://wordpress.org/plugins/tietools-automatic-maintenance-kit/" title="TIEtools" rel="ugc">TIEtools</a>, which also includes post expiry and duplicate post control.
An extremely simple plugin which removes accumulated error log files from your web space. It is VERY important to note that the plugin does no checking or any complex stuff: it just removes error logs. Please read the FAQ before you activate this plugin.

TIElogremover

An extremely simple plugin which removes accumulated error log files from your web space.

michaeltyson

Reclaim disk space and clean up your uploads folder by deleting old uploads you are no longer linking to.
This plugin will identify unused files within your uploads folder, and give you the option of archiving then deleting 
some or all of these files.
Before any action is taken, Upload Janitor will automatically make a ‘tar’ archive of all files to be 
erased, including their original paths, so you can restore if necessary.
<h3>How does it work?</h3>
This plugin inspects every file within the uploads folder. For each file, it searches pages or posts that 
reference the file. That is, the plugin searches for the part of each file’s path that comes after the path 
to the uploads folder, such as <code>2010/01/my great but forgotten image.jpg</code>.
The path is searched as-is, as well as URL-encoded with ‘%20’ for spaces, and the same with ‘+’ for spaces – 
 2010/01/my%20great%20but%20forgotten%20image.jpg and <code>2010/01/my+great+but+forgotten+image.jpg</code>. HTML entity-encoded 
forms of all of these are also searched.
If no matches are found, then the file is considered unused.
Note that this plugin plays it safe, and does not distinguish between older post/page revisions and the current version 
of a post/page. If a revision references a file, the file will be considered still in use.
<h3>Restoring</h3>
If something goes wrong, you can always restore. If you have shell access to your site, this is easy. Simply log in, 
navigate to your <code>wp-content/plugins</code> directory, and locate the Upload Janitor archive – it will look like 
 upload_janitor_archive_YYYY-mm-dd.tar.gz. Then, type:
<pre><code> tar zxf <archive name> .
</code></pre>
This will restore all files within the archive.
If you do not have shell access to your server, you will have to download the archive, extract it, then upload the 
contents back to your server. The archive will be accessible at http://your-blog.com/wp-content/uploads/upload_janitor_archive_YYYY-mm-dd.tar.gz

Upload Janitor

Clean up unused images and other files from your uploads folder.

TIElogremover vs Upload Janitor