TextPad is the way to go. I have used others, but if I am forced onto the windows platform, it is the best tool with the most support that I have found. Incidently, in addition to perl syntax high lighting, it has many more which are downloadable... and you can make your own, which is what I did when working on Adept Robots. And yes it should fit very nicely on your USB drive/key.
...the majority is always wrong, and always the last to know about it...