Omegle has been around for a while connecting random strangers in text chats.
They have added the video chat option very recently.
anybodyoutthere is a random chat service with an awesome UI and concept.
You can ask a question or share a thought and you will be shown a list of people with similar interests to talk to.
Omegle allows you to share the chat log in your Facebook account or to download it to your PC. It allows you talk to your friends or to random strangers.
One cool feature of this web app is that people who are available for a random chat are presented in 3D bubbles with their profiles.
Being in the same domain, they have launched Tinychat Next which works the same way as Chatroulette.
The user interface is a bit more refined and you need to have flash installed to even see how the UI looks like.
Created by a Russian school boy, Chatroulette connects millions of strangers in random video conversations.
The web app itself is pretty bare-bones, with two video panes showing the user & you, a huge pane for text chat and a couple of buttons for controlling the chat.
You should have a email id provided by your University or college to register and take part in a conversation.