Preventing Site Loading Delays due to ASP.NET Startup (Including DotNetNuke)

http://www.mitchelsellers.com/blogs/articletype/articleview/articleid/103.aspx

Keep Your Website Alive (Don’t Let IIS Recycle Your Website)!

http://www.codeproject.com/Articles/39118/Keep-Your-Website-Alive-Don-t-Let-IIS-Recycle-Your.aspx

Forcing an ASP.NET Application to 'stay alive'

http://www.west-wind.com/WebLog/posts/67557.aspx

Simulate a Windows Service using ASP.NET to run scheduled jobs

http://www.codeproject.com/KB/aspnet/ASPNETService.aspx