If you are looking for a thematic and original set of social bookmarking icons, here comes an option for you.

Social Lego is a set of 20 icons, built exclusively for WRD readers by Iconshock (same creators of WordPressThemeShock), that has a lego-like texture and includes the items for the most popular social services like Facebook, Twitter, Google+, Youtube and much more.

The set comes as .PNG and .AI vector formats where you can create any size and modify the easily.

It is free to be used in both personal and commercial projects (and can not be redistributed).

P.S. If you share this icon set in your website/blog, please link to this post rather than the download link. Thanks very much for that.

Picons.me, an icon design company offering various icon sets, is sharing a set of 60 social icons for free.

The set has items for all the popular social networks and comes in multiple vector formats: .AI, .EPS, .PDF.

There are also .PSD + .CSH versions and .PNG in 8 different sizes (from 16*16px to 512*512px).

P.S. In order to prevent any confusions, the resource's website mentions that the Picons.me license doesn't apply to this social set.

Plastique Icons is a set of 100+ free vector icons that includes variations of popular items like file, folder, database, calendar, etc. and many other unique ones.

The set is colored black & white color and comes in .AI format so it can be resized or the colors can be changed completely.

There is also a sprite (48*48px) with the CSS rules is provided for easier usage on web pages.

For anyone developing Android applications and/or creating an Android-related website, using the official icons for the platform would be a time-saver.

The Android SDK includes the complete set of icons, however, they are in .PNG format and hard to resize or customize.

Olof Brickarp, who is a UI/graphics designer, has converted most of the whole official icons into vector formats which are now available in .AI, .EPS and .SVG.

Roam Design, an award-winning creative marketing consultancy, is sharing 99+ Icons which is a set of slick, monochrome and vector icons.

The items in the set include actions, media, devices and mobile-specific ones like battery status icons.

99+ icons comes as a .AI file and it is free to be used in personal projects (or in commercial projects with a link back).

IconShock, the well-known icon design company, is sharing a huge set of free credit card icons.

The set consists of 61 icons including almost every possible payment processor (MasterCard, Visa, AMEX, PayPal, Google Checkout, etc.).

They come in 3 formats:

• .AI
• .PSD (24*24px, 32*32px, 48*48px and 64*64px)
• .PNG (24*24px, 32*32px, 48*48px, 64*64px, 128*128px, 256*256px and 512*512px)

All items are pixel perfect and can be used in both personal + commercial projects.

Alex Peattie, a talented freelance web designer and developer, has created a high-quality and vector social icons set.

The set has 100 icons and includes items for every major social network (Twitter, Facebook, Delicious, YouTube and many others).

They are provided as:

• a whole in .AI + .EPS formats (90px*90px on 100px*100px artboards)
• individual files in .PNG (32*32px) and .SVG formats

The icon set can be downloaded from WRD:

or from Alex Peattie's website.

This vector social icons set is free to be used in both personal and commercial projects.

WPZOOM, a website providing premium WordPress themes, is sharing a set of 154 beautiful and free icons named WPZOOM Developer Icon Set.

The icons are flat, black & white colored by default and come in vector formats (.AI & .PSD – so, color is not an issue) besides .PNG (48*48px size).

The set contains many different items from documents to social networks, devices to actions.

Simply, it is built with developers in mind and a very suitable set for web apps.

MIX Online, a Microsoft-powered website on web design and development, is sharing a free Adobe Illustrator plugin for converting .AI files into HTML5 canvas.

AI->Canvas plug-in offers options for drawing, animation and coding, such as "events" so that you can build interactive, well-designed canvas-based web apps.

It can be used to export simple-to-complex shapes, gradients, transparencies, drop shadows and any other stuff.

And, the animation features include rotation, fades, movement, easing, triggers and more.

AI->Canvas comes with versions for Windows + Mac.

IconShock, a well-known icon design company, is sharing an impressive and complete social bookmarking/networking icon set.

The set has ~150 unique items in 9 different pixel-perfect sizes and they are all available in .PNG, .PSD, .AI and .ICO formats.

Also, for mobile applications, there is a "mono version" included as well.

That's not all. Every icon has 3 color states: enabled, disabled and normal. Simply, a must bookmark.