NUnit to Write Unit Tests http://www.nunit.org.
Ndoc to create code documentation http://ndoc.sourceforge.net
Nant to build your solution http://nant.sourceforge.net
Codesmith to generate code http://www.ericjsmith.net/codesmith
Fxcop to police you code http://www.gotdotnet.com/team/fxcop
Snippet Compiler to Compile Small Bits Of Code Http://www.sliver.com/dotnet/snippetcompiler
Two Different Switcher Tools, The ASP.NET Version Switcher and The Visual Studio .Net Project Converter http://www.codeproject.com/macro/vsconvert.asp
Regulator to build regular expression http://royo.is-a-geek.com/regulator
.NET Reflector to Examine Assemblies http://www.aisto.com/roeder/dotnet
