Notepad++

Notepad++ is a good free text editor for programmer, which supports several programming languages and has many cool features. 

Features

• WYSIWYG
• User Defined Syntax Highlighting
• Auto-completion
• Multi-Document
• Multi-View
• Regular Expression Search/Replace supported
• Full Drag 'N' Drop supported
• Dynamic position of Views
• File Status Auto-detection
• Zoom in and zoom out
• Bookmark
• Brace and Indent guideline Highlighting
• Macro recording and playback

Support language

C, C++, Java, C#, XML, HTML, PHP, CSS, makefile ASCII art (.nfo), doxygen, ini file, batch file, Javascript, ASP, VB/VBS, SQL, Objective-C, RC resource file, Pascal, Perl Python, Lua, TeX, TCL, Assembler, Ruby, Lisp, Scheme, Properties, Diff, Smalltalk, Postscript, VHDL, Ada, Caml, AutoIt, KiXtart, Matlab, Verilog, Haskell, InnoSetup, CMake

Plugin

Notepad++ also has many free plugin such as Function lists, Insetion, XML tool, Hex editor and more, you can see on a donwload page. 

Download: Notepad++