1. ProNotepad 2 (http://sourceforge.net/projects/pronotepad/)
ProNotepad 2 has some quick tools and tabbed browsing/editing feature.
2. Notepad++ (http://notepad-plus.sourceforge.net/uk/site.htm)
Notepad++ is a free open source text editor that features syntax highlighting, multi-document view and you can even drag and drop files.
3. Notepad 2 (http://www.flos-freeware.ch/notepad2.html)
Notepad 2 is another substitute for the legendary Windows Notepad. It makes itself unique as it runs out of box without any installation and does not touch your system registry. It also has syntax highlighting.
4. Metapad (http://www.liquidninja.com/metapad/)
Metapad is a sweet Windows Notepad replacement that is small and fast. It has all the features of Microsoft Notepad plus some extra added features.
5. NoteXpad 2.0 (http://ryan.ript.net/notexpad/)
NoteXpad 2.0 is a replacement application for Microsoft Windows 5.0 and higher. It features command line open, insert date/time stamp on document and remembers screen position and size.