An icon is a small picture used on a screen to represent some action or content. Icons can be used alone or with words. By themselves, icons can save space. A very visual icon can often say more in a few pixels than even a few words can. Icons retain some advantages over textual links. They are often easier for users to recognize than words.

As the Web grows, some icons will certainly become commonplace and their meaning fairly well understood. Most of these icons will probably owe some heritage to desktop applications, but some may be new. The particular style for the icon is inconsequential. Consider the shape to be the primary focus of the icon.

Project Icons

By Navdeep Raj. Via Smashing magazine.

Sketchy Icons

Via Double J Design.

Coquette Icons

Coquette- a free icon set contains 50 high quality, free icons. Via dryicons.

E-commerce Icons

By Starfish Web Consulting.

Bright

Bright! is a crisp, sharp and beautiful set of 148 hand-crafted icons in vector format, ideally for both web and print work.  Via Min's Blog.

Grace Icon Set

The soft shades of black and white selection of colors makes this icon set graceful, unique and extremely stylish. The icon structure consists of snow white leaves, flowers and swirls. Get creative with these free icons and enjoy the changing of seasons. This free icon set contains 80 high quality, free icons. Via dryicons .

Onebit Icon Set 1

A comic-look icon set, non reflective or glossy can be used for your web development project. Via Icojoy.

Onebit Icon Set 2

Via Icojoy.

Artistica Icon Set

Artistica Icons are hand-drawn using bright and fun colors. Via dryicons.

Financial Icon Set

This set contains useful and flexibly applicable icons as application and financial symbols, and the set surely will make your web applications and software more attractive and adorable. Via Iconeden.

Pixel Mixer Web Development Icon Set

42 high quality icons for your web application, software or GUI design. Via PixelMixer.

Phuzion Icon Pack

Phuzion Icon Pack contains 150 high quality icons. This package includes: Apps Icons, Disks & Drives Icons, Extras Icons, Folder Icons, File Types Icons, Misc Icons, Signs & Symbols Icons, System Icons and more. Via VistaIcons.

Futuristica Icons

This unique and useful icon set will help you bring attention and show your creativity in your projects. This free icon set contains 20 high quality, free icons. Via dryicons.

WP Woothemes Ultimate icons

Via iconspedia.

Hand Drawing icons

If you like cool handwriting icons, you may want to consider them. By Aleksandra Wolska. Via iconspedia.

Business Vista icons

These beautiful commerce icons make your business comes to life. By Aha-Soft. Via iconspedia.

Clear Bubble Icons

By WebTreatsETC. Via iconspedia.

Heart Shaped Social Media Icons

Via Custom Icon Design.

Sketched Social Media Icons

Social Media in a different feel. By Plechi. Via deviantart.

Jeans Social Media Icons

By Nishad. Via deviantart.

WP Woo Themes Icon Set

By Nishan. Via WP Woo Themes.

Sekkyumu's Developers Icons

By Sekkyumu. Via deviantart.

Origami Icons

By Jack Cai.  Via Icon Dock.

iD Icon Pack

Via Delacro's Blog.

Black and White Pixel Web Icons Set

By Paul Armstrong.

Fugue Icon Pack

Comprehensive pack of icons for spoil for choice. By Pinvoke.

Pixel Web Icons Set

By Paul Armstrong.

Mini Pixel Icon

Via Icon Dock.

Xiao Icon

Classic icons always a safe bet. Via Delacro's Blog.