I have a script on GM that I would like to add color to on the info page. I tried copying the pre area with all the spans and all the style's independently but userscripts doesn't let me add style tags. Is there a site or util that I can paste my code and it will color it with inline css coloring?
I´m not 100% sure if I understand what you are asking for, but if you are thinking about syntax highlighters in Javascript, there are quite a few out there.
If you want an online tool that adds highlighting for you and outputs html, here is a nice one. If you want a web service, then I´m sorry, I don´t know of any, but it would be awesome if someone did.