Normally when you click on a link to a file the browser will try to read or open that file automatically. This code will force the browser to open the "Save As..." dialog box using a swf file as an example.
<%
response.ContentType="application/x-shockwave-flash"
response.AddHeader "content-disposition","attachment; filename=button1.swf"
server.execute("button1.swf")
response.End()
%>