Use Response.Redirect to open a new window

I can't find a way to do this in .NET, do I have to use javascript? Thanks.

Yes.
The server doesn't have a window.
A window is a client-side object.

You can use javascript in .net and have it run on the client...

Oh, and please keep in mind that tabbed browser users may hate you. :D
If I want a new window, I'll middle-click and open one.