Origami Icon Set

Origami is a set of 15 vector icons designed by Jack Cai from Double-J Design. The icons come in 5 different sizes (16px, 32px, 48px, 128px) and available in both .ICO and .PNG format. [link]

Flavours Icon Set

German designer Oliver Twardowski designed and released this icon set exclusively for Smashing Magazine aiming to help designers enhance their user interfaces for their websites or web applications. The icons are 48 x 48 pixels and come in .PNG format as well as .PSD format so you can modify the files to your preference. [link]

Free Social Media Icons from WeFunction

A set of social media icons by WeFunction including icons for popular social networking services such as Digg, Facebook, and Twitter.  [link]

Grungy Aesthetica Icons

A set of 181 high-quality web icons in transparent .PNG format designed to compliment grunge-styled websites and blogs. Available in 32px, 48px, 64px, and 128px sizes. [link]

20 Blockie Icons

Here is a set of 80 icons (20 icons available in 4 colors) that can be used in desktop interfaces, web applications, and blogging themes. The icons come in 5 different sizes (16px, 32px, 48px, 128px) and available in both .ICO and .PNG format. [link]

Coquette Icon Set

A set of 50 high-quality cartoonish icons. These colorful icons are perfect for any web project and are available in both .PNG and .ICO file formats. [link]

Round Social Media Icons

Here is another set of social media icons. This set is designed by Eli Burford and is available in 3 sizes for 17 icons (32px, 64px, and 128px) [link]

Sketchy Icons

Another set of social bookmarking icons but this time in a cool pen sketch style. They are available in 3 colors: blue, black, and transparent blank all in .PNG file format. [link]

Web Injection Icons

26 stylish icons designed by Jonatan Castro Fernández from Midtone Design Studio. This set includes RSS feed and database icons perfect for web developers and application builders. [link]

Practika Icon Set

11 free web icons designed by DryIcons. The icons are available in 3 sizes (64px, 128px, 256px) in transparent .PNG format. [link]

Stickers Icon Set

A set of curvy dark gray color-schemed icons with white borders available in 5 different sizes (16px, 32px, 48px, 128px) and available in both .ICO and .PNG format. [link]

Vector Icon Set by Monofactor

25 scalable Adobe Illustrator format icons. You must have Adobe Illustrator to open and modify .AI files. [link]

Facebook UI Styled Icons

High resolution vector icons imitating the Facebook UI by deviantART user lopagof. [link]

Project Icon Set

18 vector icons designed by Navdeep Raj for business or corporate blogs. This set includes an address card, bar chart, portfolio, calendar and many more icons. The Fireworks source files are available as well. [link]

Onebit Icon Set

A set of 50 simple and colorful icons by Khodjaev Stanislav. Available in .PNG file format 48×48 only. [link]

Handycons 2

Handycons is a set of 20 unique hand drawn social media icons. The icons come in 4 sizes: 16px, 32px, 64px, and 128px. [link]