Everybody loves free. This is especially true for something of value and the icons we’ve listed below have just that. If you’re a designer or developer, you can’t go wrong with adding some spice to your design or application using any of these icons.

Click the images to visit the source. And please remember to read the specific licenses for each set and use accordingly. Enjoy!

Social Media

Social Network Icon Pack

Created by Rogie King, this has to be one of the nicest sets of icons for social media, both in depth and quality. Each icon looks smashing and with over 40 social applications included, you should be covered.

Feedicons

Over the past couple of years, there has been a glut of free RSS based icons made available. Many were large and glossy and somewhat garish. Not these — this set contains 69 icons that are very tastefully done.

Social Bookmark Iconset

There are two packs here, containing icons for most bookmarking or link-sharing web applications.

Social Web Buttons

In the same vein, this set contains button icons for bookmarking services.

Handycons 2

This unique set is hand drawn and consists of 20 icons for social web applications.

Polaroid

Another great looking group of social web application icons, all made to represent a polaroid photo.

Free Glossy Social Icons

From the same source, here’s another set based on these web services. This pack resembles iPhone application buttons.

Applications

WYSIWYG Sapphire

A nice set of application icons, perfect for an online editor.

Free Vector Set from monofactor

This a simple and clean set of 25 icons, all in vector format.

WebAppers

This is a more cartoonish set for use in an application.

WebInjection

Here’s a great set of detailed icons that could be used in an application or a new web design.

Danish Royalty Free

This is an exquisite set of all purpose icons that would nicely adorn a web application.

iPhone

OpenPhone

A gorgeous set of icons for mimicking the app buttons on the iPhone interface.

iPhone Template and Material

This site provides a lot of backgrounds and icon examples for working with the iPhone. They could also be used in other implementations as well.

GLYPHISH

This is a widely used set of icons that, as the creator describes, can be used for “Designed and carefully optimized for use on toolbars and tab bars in iPhone apps, they’re also perfect for Android apps, websites, t-shirts, tattoos and more.”

Well said.

General Web Design

ROUNDer

An interesting set of 43 icons that cover a lot of different web and desktop tools.

Gmail from iconaholic

A nice set of icons for everyone’s favourite web mail application.

Iconshack

Check out the full list of icons from this designer. Plenty to choose from, but here’s our favourites.

Banking Icons

Mac Web Icons

Office Icons

Construction Icons

Shutterbug

A nice set of photography related icons.

iconeden

This site has a number of great free offerings that work well for web design.

Bright

Here’s a good all around set perfect for print or web design.

Fresh

This one is a great set of financial related icons.

Milky

Another professional set that covers multiple themes.

Birdies

And lastly, here’s a nice set based on Twitter.

Ruby on Rails

This small batch of icons are perfect for any Rails-related projects.

Office Space

Yes, I’m a sucker for icons of cups of coffee …

The City Icons

A funky batch of mixed icons in png and ico format.

Bagg and Boxes

Another interesting set, this one includes a lot of laptop and camera related icons.

Wheat Icons

This group of icons were intended for the Menu bar in OS X, but they actually work well in other situations.

Sidebar Replacements

Another set intended for use in OS X, there are PNG files included that would nicely spruce up a web design.

Token

Consisting of 128 icons in dark and light, this beautiful set could be used in various forms of media.

The End

The web can be wonderful place, especially when talented individuals share their hard work. I hope you enjoy putting some of the icons to good use!