Possible Duplicate:
Allow highlighting certain bits of a code fragment or quote
In dealing with a wall of code, it would be handy to be able to paint some of it red, or bold, or something. Editing the question to highlight the part that actually matters can be an effective part of answering.
Since the syntax highlighter knows from comments, you could recognize:
//SO:YO
//SO:OY
as matching delimiters (using whatever comment syntax is active).