ASCIIDraw by Fredereic Lebel, is an useful application made to produce all kind of character based graphics, such as ASCII art, roguelike user interfaces, and generally anything you would otherwise do using a text editor, with the difference you can use back and fore color and pick your symbols easily. It is currently been worked on and evolving pretty well.
AsciiDraw is a console application meant to serve as a replacement for standard
text editors when prototyping a roguelike’s interface. It provides access to
all ascii characters and standard colors.
+ Use it to quickly test color schemes for dungeons and interfaces.
+ Try out room, corridor and outdoor designs without having to code them.