Programmer's Notepad is a very powerful text editor featuring syntax highlighting, project management, a great UI and much more.

Programmer's Notepad Features:

Bookmarks (both numbered and plain)
Code Folding/Outlining
Docking tool windows - much better than those in version 1
Excellent external tool support with user-configurable output matching - click on errors and warnings to jump right to the place in the file where they were generated
Export to HTML (using CSS) and RTF
File association manager
In-file method/definition navigation (using Ctags)
No limit on file size (although large files may take a while to load)
Non fixed-width font support
Projects and Project Groups with multi-level folders and file system mirroring
Quick Search toolbar with links to Google and Google Groups
Regular expression search and replace
Support for unicode files
Support for windows, unix and macintosh file formats
Syntax highlighting for many languages through "schemes".
Tabbed MDI interface
Text Clips
Unlimited number of schemes supported, powerful syntax highlighting supporting both user-defined and built-in schemes
User-defined schemes (XML)
Word-wrapping