I find myself frequently highlighting and formatting portions of text cells in a Mathematica notebook. Bold and Italic typesetting is easy to handle but I would like to use backticks to provide formatting similar to the SE editor or perhaps use underscores and asterisks to auto-format in other ways (say for example, text within ** here ** would be red and text within _ here _ would be highlighted yellow.
Is it possible to customize a stylesheet to afford this type of formatting?