I always use
* JJ - DEBUG - START
Code block
* JJ - DEBUG - END
Then change it to my standard defect comment when I'm ready to check stuff into source control. Helps me find stuff I'm working on.
>I do pretty much the same - I comment out pieces of code, and wait about a dozen iterations before deleting stuff. I also write a comment explaining why is this commented out, so when the time comes to clean up, I know why was it there, and why (or whether) it should vanish.
>
>As for the !!! - accidentally, I've done exactly that today for the first time; my traditional mark was $$. Another habit is one I picked from Steven Black:
>
>*!* !!! KLUDGE ALERT !!!
>
>He uses that (albeit he spells it "KLUGE") for special cases when there's a need for a nasty workaround, going against the framework, or there's a hotfix patch which would need to be done right once time permits. And, of course, there's a matching "END ALERT" comment after that block of code.