http://www.bayden.com/SlickRun/
SlickRun is a free floating command line utility for Windows. SlickRun gives you almost instant access to any program or website. SlickRun allows you to create command aliases (known as MagicWords), so C:\Program Files\Outlook Express\msimn.exe becomes MAIL.
Enter a web URL into SlickRun and it will launch your browser and navigate to the specified address. Run multiple programs in a few keystrokes, jot a note, look up a definition... SlickRun is the most natural way to interact with your computer.
2. Vim + Cscope
http://www.vim.org/
http://cscope.sourceforge.net/
There are a lot of useful plugin for vim too.
3. Monad
http://www.pcpchina.com/download/msh_x86_beta1.zip
and here is the .NET framwork
www.microsoft.com/downloads/details.aspx?FamilyID=7ABD8C8F-287E-4C7E-9A4A-A4ECFF40FC8E&&displaylang=en
Next generation command line tool for windows, instead 'cmd'
4. startdict
http://stardict.sourceforge.net
A useful free dictionary.