Something like coda ( http://www.panic.com/coda/ ) or textmate for windows!!
It would be great if you could create a text editor with a clean interface like coda, textmate, and espresso have. There aren’t any cool text editors available for Windows. I use e-texteditor myself, but I don’t really like it. People tend to switch from pc to mac just because they then have proper text editing software. For me, $2000 is a little too much, but I’m willing to spend up to $100 on a proper text editor.
If you focus on the interface, you’ll get a lot of sales It should definately support code-coloring and perhaps snippets and ftp. I know that this is a LOT of work, but it’s just a suggestion