Digg

Digg is a social news website made for people to share content from anywhere on the internet by submitting links and stories, and voting and commenting on them. Many stories get submitted every day, but only the most Dugg stories appear on the front page.

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Del.icio.us

A free service where people store their bookmarks, favorite links and resources, enabling you to see what's trendy and popular.

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LinkedIn

LinkedIn is a social networking website geared towards companies and industry professionals looking to make new business contacts or keep in touch with previous co-workers, affiliates, and clients.

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MySpace

MySpace is a social networking website where you can: Find friends & classmates, meet new people, listen to free music & build playlists, share photos, watch videos, start a blog, read celebrity news, get cool apps, free IM & more

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Four Square

Foursquare allows you check in, find your friends and unlock your cities. 

On your mobile phone it gives you and your friends new ways of exploring your city.

Think of it like a city welcome guide meets twitter. It allows you to “check-in” whenever you go somewhere: the grocery store, the mall, a conference out-of-town, a restaurant, a bar…you get the idea.

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Google Buzz

Google buzz reminds us of an RSS combined with all of your social networking. It can be used on a PC or mobile phone.

There are five key features which include:

• Automatic friends lists (friends are added automatically who you have emailed on Gmail)

• "Rich fast sharing" combines sources like Picasa and Twitter into a single feed, and it includes full-sized photo browsing

• Public and private sharing (swap between family and friends)

• Inbox integration (instead of emailing you with updates, like Facebook might, Buzz features emails that

update dynamically with all Buzz thread content, like the photo viewer we mentioned above)

• "Recommended Buzz" puts friend-of-friend content into your stream, even if you're not acquainted. Recommendations

learn over time with your feedback.

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StumbleUpon

StumbleUpon is an Internet community that allows its users to discover and rate Web pages, photos, and videos.

Web pages are presented when the user clicks the "Stumble!" button on the browser's toolbar.

StumbleUpon chooses which Web page to display based on the user's ratings of previous pages,

ratings by his/her friends, and by the ratings of users with similar interests. Users can rate or choose not to

rate any Web page with a thumbs up or thumbs down, and clicking the Stumble button resembles "channel-surfing" the Web. 

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