Possible Duplicate:
What is your single favorite development tool?
Every day I realize how much I love Visual Studio for .NET development.... but, I believe that Resharper, may hold a value that surpasses Visual Studio's (I am using VS 2005 for WPF/WCF development).
I decided it would be great to compile a list of the most valuable tools for software development. These can be applications/plug-ins anything that you think holds GREAT value.
Also, please explain the benefits of the tool that you are posting.
Resharper:
- Intergrated Unit testing
 - "Camel Hump" code auto completion
 - Find "usings" (inverse of "Go to Deceleration")
 - Code formating and member rearranging
 - Assembly and namespace inclusion (based on your code)
 - Check for common optimizations and possible bugs in code and suggests/rewrites the code for you (things like null checking, redundant delegate creation, inverting if statements, etc...);
 - Tells you when code and be more generic (may suggest things like "use this interface instead" if your code never refers to something specific on an object)
 - Helps you see code that is not being used and will clean any unused members.
 - File structure view helps you jump around the regions of your file (this is really awesome and clean).
 - Class searching (you can use things like camel humps) Asks you which partial file to open once you find a class.
 - It also has it's own plugin support, so you can do things like FxCop, documentation and relfector (all free).
 - This thing has so much I don't think I hit 10% of it yet :) [When I get time, I will try to add more... feel free to help me out]