AJAX in ASP.NET 2.0
Make asynchronous, out of band, client callbacks from your ASP.NET 2.0 application.

AJAX (Asynchronous JavaScript and XML) Tutorial
Make asynchronous, out of band, client callbacks from your ASP.NET 1.1 application to update portions of web pages without rendering the complete web page.

Upload files from client PCs to a web server with ASP.NET
Upload files from a local, client PC to the web server with ASP.NET using the "System Web UI HtmlControls" namespace's "HtmlInputFile" server control.

Change the cursor to a Wait cursor in ASP.NET
Change the cursor to a wiat or hourglass cursor on your ASP.NET web page.

Conditionally set properties of web pages controls with the Databinder in ASP.NET
The Databinder class of the System.Web.UI namespace lets you dynamically create bindings between any property on an ASP.NET page, including server control properties, and a data source.

Embed client side JavaScript in ASP.NET 1.1 pages.
Embed client side JavaScript in ASP.NET 1.1 web pages from your code behind with the "RegisterStartupScript" and "RegisterClientScriptBlock" commands.

Embed client side JavaScript in ASP.NET 2.0 pages.
Embed client side JavaScript in ASP.NET 2.0 web pages from your code behind with the "RegisterStartupScript" and "RegisterClientScriptBlock" commands.

Determine if ASP.NET's Session Object has timed out.
ASP.NET lets you pass user specific data between web pages using the "Session object" but uses a timeout feature to discard a session information. See how to detect if the session has timed out.

Format data in a bound DataGrid on an ASP.NET web page.
The ASP.NET DataGrid's BoundColumn control lets the data displayed be formatted via the DataFormatString property.

Programmatically loop through an ASP.NET Datagrid to retrieve cell values.
See how to loop through an ASP.NET Datagrid with both server side code and with client side JavaScript to retrieve cell values when the cells contain plain text or controls such as textboxes and checkboxes.

Set focus to a specific control on an ASP.NET web page.
With a little JavaScript you can set the focus to a particular control on your ASP.NET web page.

Use the HTTP Cache in ASP.NET web pages to improve performance.
ASP.NET lets you cache static data in the web server's memory dramatically improving web page performance instead of reading it from a file or database each time it is needed.

Understanding and working with cookies in ASP.NET.
Learn about the idiosyncrasies of the Request and Response Cookie objects in ASP.NET and how to correctly use cookies avoiding the common errors.

Issue a modal JavaScript dialog from ASP.NET server code.
See how to conditionally issue a modal JavaScript Alert dialog from your ASP.NET page's codebehind.

Save a DataSet to Excel in ASP.NET and allow the user to open or save it.
In ASP.NET, you can create a DataSet, export it to a file as XML, then allow the user to open or save the file from their browser.