The Jake Group

This plugin allows you to change the words “Posts” and “Pages” in the admin 
interface to anything you’d like. Plural inflection is currently not 
supported… sorry… no geese or boxes for you! Choose your new term in the 
“Rename Posts/Pages” panel. This plugin requires PHP 5.

Posts/Pages Admin Renamer

Allows a user to change the words "Posts" and "Pages" in the admin interface.

Kinski &amp; Bourke

This is a super simple plugin for uploaded file name sanitization.
Essentially, it’s to make your uploaded filenames easier for search engines to read, hence better for SEO, nicer to look at in the folder (who cares?), and should also help avoid any issues with naming conventions. 
You might be thinking that WordPress does a good enough job at renaming, but it still allows underscores and other symbols and characters that maybe don’t belong in a filename.
e.g. 
This: Æ, %20 æ Ï, Ö, Ü, Ÿ-boyz_%20__=++&, ©, §)+Ţ ţ++‰+ath-club-ÆØÅæøå–.pdf 
Becomes: AE-20-ae-I-O-U-Y-boyz-20-T-tath-club-AEOAaeoa.pdf 
This: —-___——]- hair space U+200A.jpg 
becomes: hair-space-U200A.jpg
The Original idea for this was done by Vaughn Royko and so we thought we would turn this into a simple plugin with a few options for those who are worried about messing with their functions file, and or can only install plugins and cant edit the Functions file.

SEO File Renamer

Very helpful and smooth plugin. Recommended!

Amazing plugin

A super simple plugin for uploaded file name sanitization.

Posts/Pages Admin Renamer vs SEO File Renamer