Best way to update value on the client's page WITHOUT refreshing the page
 

Ok the clients loads a page where he is given address to send electonic payment via client outside the browser.
As soon as the server sees the deposited money, it should update clients balance on the page WITHOUT the need the user to refresh the page.

What's the best way/technology to do that?

The Firefox has the tool to update value.

omg.......... :)

Use AJaX, With Ajax, web applications can send data to, and retrieve data from, a server asynchronously (in the background)