Just noticed this at DOtNetJunkies blogs - most interestring link to me was this one which links to the MSDN Regional Directors code center , just a shed load of useful utils there!

 Look what I have found :)

ASP.NET server side Back control by Juval Lowy

Common techniques for implementing a Back link on a web page involve using the browser-side script. There are a number of disadvantages to this solution: the application has no control over where the user is going to be redirected. Often you want to keep the user inside the application, and you do not want them to wonder off to other pages, and it only works if the browser supports client-side script. The biggest disadvantage is that it is not consistent with the ASP.NET programming model of server-side controls. There is also no easy way to enable or disable the back link based on server-side event processing. The download contains a server-side user control, which provides the Back functionality. Simply add it to your toolbox, and drop it on your forms. I love to use this :) One can find one more control similar to this, here.

Apart from this, find some of the most sought after utilities like Remoting Toolkit, Mail Checker, Detailed SQL Error Messages and loads and loads of them here :)