AkelPad - is an open source editor for plain text. It is designed to be a small and fast.
Features
Single window mode (SDI), multi window mode (MDI);
Editing of files, which size is more than 64K (generally speaking, size isn't theoretically limited);
Full support of Unicode strings on Unicode systems (NT/2000/XP/2003);
Support of Unicode codepages (UTF-16 little endian, UTF-16 big endian, UTF-8);
Support of any codepage installed in the system;
Support of DOS/Windows, Unix and Mac newline formats;
Preview file open;
Correct pseudographics displaying;
Column text selection;
Multi-level undo;
Fast search/replace text strings;
Remember file codepage and caret position;
Printing of a document;
Support of language modules;
Plugins support (syntax highlighting, auto-completion, scripts execution, keyboard macros and much more).
Screenshot (basic)
Screenshot (plugins)
Sourceforge.net project page