Tracing web application with ASP.net

Do you like debugging? How hard is for you to figure out what is crashing and where? Usually we use lots of "response.write" lines of code or breakpoints, but that requires special development conditions and usually cannot be performed on the QA servers or even more: on production servers. "Tracing" your applications might help.
The following links explain what Tracing is about and how can we use it in .Net.

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dnaspnet/html/asp01252001.asp

http://www.codeproject.com/useritems/Tracing_Explained.asp