23 freeware “iPhone-like” icons of Web 2 Social Bookmarks and Networks for use in blogs, websites, desktops, softwares.
The Linux version includes .PNG files sized from 512X512 to 16X16 pixels. Great for Bloggers.

Content:
Blinklist, BlogMarks, Delicious, Digg, Diigo, FaceBook, Favorite, Feeds, FeedBurner, Flickr, Furl, Google Magnolia, Misterwong, Myspace, Newsvine, Netvibes, Reddit, Simpy, Stumbleupon, Technorati, Twitter, Youtube.

Web 2.0 Icons By Nicolai

Download host of web 2.0 style icons in thumbnail form as well as large sizes for your use for free (speech bubble, chart, home, computer, email, globe, rss, butterfly, printer, cell phone, security, wine bottle)


iconGalore

Windows XP Style Icons designed as per Microsoft standards are available for free for non-commercial purposes

Web2.0 site’s logo: Here you will find 3D like logos for the popular web 2.0 sites like del.icio.us, flickr, youtube, technorati, feedburner and also an icon for rss. The images are available for free usage and can be downloaded as a zip (which has png and ico versions of the files)

Yellowpipe.com: has a comprehensive collection of icons for Mac, Mac Office, Windows (XP icons, Vista icons), Linux(Gnome, Tux) etc.