All plugins are freely available via the WordPress.org repository. You can search and install them directly from your blog “Plugins” administration panel.
Head and Footer and Post Injections
Simple and flexible, Head and Footer plugin let you add any kind of script on the HTML head page section or on the footer part. More you can add content and/or scripts before and after posts and configure some of the Facebook Open Graph metatags to have a better rendering of likes on Facebook walls. In my opinion, this plugin is a must-have and can easily replace a lot of service-specific plugins.
Go to the Head and Footer plugin official page.
Include Me
The Include Me plugin is the evolution of the Include It and lets to include external content inside a page or post. External content? Yes, for example, an external PHP file is loaded and executed and the result is injected inside the page. Alternatively, Include Me can generate an IFRAME (even if with the latest version of WordPress editor IFRAMEs seem to be better supported – the older version scrambled the IFRAME tag). I found it very useful to make pages that include a complex script of external services, like chat areas.
Newsletter
A complete mail marketing system for your blog. This plugin is now maintained in collaboration with some friends. The core functionalities (many!) are part of the free plugin, but advanced users can get specific commercial add-ons.
Go to the Newsletter plugin’s official site.
Thumbnails
Helps to have perfect thumbnails with each theme. This plugin generates thumbnails on the fly when a theme or plugin asks for a specific image size and crop. The generated resized picture is stored in a cache without clogging up the media folder.
Go to the Thumbnails plugin’s official page.
Hyper Cache
Hyper Cache is the first caching plugin I worte for WordPress (not the last) and as far as I know, is widely used with success from many blogs. I know there are other more advanced cache plugins but some users reported me that Hyper Cache is working better for them… so I’m keeping it live but without adding complexity: most blogs do not need complexity, only a bit more performances. Another cache plugin I worte is Lite Cache: I use it on some high traffic blogs I maintain.
Go to Hyper Cache official page.
Comment Image
Add image support to WordPress comments.
Go to Comment Image official page.
Comment Notifier
Adds notifications to WordPress comments.
Go to Comment Notifier official page.
Post Layout
Post Layout (the pro version is now merged with the free version) gives you control on code injection in the post content. It is perfect to inject ads, social buttons, noticies and so on.
It has a per category configuration to inject different code in different categories. Can be anbled to let authoer having thait own injection configuration. Note that most of the Post Layout features can be obtained with Header and Footer.
See the Post Layout official page
Unsupported plugins
Many plugins I wrote in the past are no more useful and have been removed from the WordPress.org repository (by my request). If you are still using them, consider finding an alternative.