Anthony Acosta

Provide visitors to your site the the option of increasing or decreasing the size of text by clicking on an icon which represents larger or smaller text.
Usage is simple. You can insert the code <code><?php if(function_exists('wptextsizerincutil')) { wptextsizerincutil(); } ?></code> where ever you would like the icons to appear.
NOTE: Some text will not resize if it uses an absolute size (pt) rather than a relative size in the CSS. This plugin will only resize text elements within the “content” div tag. If you are not using a div tag called “content” this plugin will not work for you.NOTE: Some text will not resize if it uses an absolute size (pt) rather than a relative size in the CSS.
All the information (general, changelog, installation, upgrade, usage) you need about this plugin can be found here: <a href="http://kennedymedia.com/wp-text-sizer" title="WP-text-sizer Readme" rel="nofollow ugc">wp-text-sizer Readme</a>.
Changes. Original code looks for the CSS “toparticle”, this has been corrected so that it searches for “content”.
<h3>Development Blog</h3>
<a href="http://kennedymedia.com/wordpress/" title="Kennedy Media's WordPress Plugins Development Blog" rel="nofollow ugc">Kennedy Media’s WordPress Plugins Development Blog</a>
Version 1.1.1 Fixes php shortform tags (Special thanks to Peter Fraterdeus for pointing this error out)

WP-Text-Sizer

Provide visitors to your site the the option of increasing or decreasing the size of text onclick of image or text links using JavaScript.

Samuel Wood (Otto)

Normally when you upload an image to a WordPress site, it creates several differently sized versions of the image automatically. Themes can define custom image sizes as well, increasing the amount of images generated on your server.
This plugin changes the way WordPress creates images to make it generate the images only when they are actually used somewhere, on the fly. Images created thusly will be saved in the normal upload directories, for later fast sending by the webserver. The result is that space is saved (since images are only created when needed), and uploading images is much faster (since it’s not generating the images on upload anymore).
“Pretty” permalinks must be enabled for this plugin to function.
Note: This plugin does not work on multisite setups, due to the way WordPress handles file serving in such situations (with ms-files.php).
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Dynamic Image Resizer

Make your images change sizes dynamically.

WP-Text-Sizer vs Dynamic Image Resizer