I used Notepad 2 by Florian Balmer for a long period of time when I took up programming as a hobby. This was because It was the most visually appealing and minimalist editor I could find that did the simple job of highlighting code, managing indentation etc on Windows. Demo with PHP.
Eventually though I wanted something a little better. I'd looked at stuff like Notepad++ and E-TextEditor (a paid-for Windows clone of TextMate) but neither were great to use — feature-wise they were sound, but the appearance of both applications was a little clunky.
So then I came across gedit for Windows. It's great. When I last used it on Ubuntu I found it awesome to use, so this was a pretty perfect find. Well supported, very stable, skinnable, supports tonnes of programming languages and has built-in plugins (written in Python, which is pretty great) that do just about anything. Oh, and all for free!
I love using it. I tweaked the twilight theme found in this pack to my liking, and the result is a pretty damn awesome looking fully-featured syntax highlighter. On Windows!!11! Huda thunk.
gedit for Windows: http://live.gnome.org/Gedit/Windows
