One comment style in C++/Java etc is this:
// Use // for all normal comments...
// and use multiline comments to comment out blocks of code while debugging:
/*
for(int i = 0; i < n; ++i) {
// If we only use // style comments in here,
// no comment here will mess up the block comment.
}
*/
I think it is an interesting point, even if it's not that incredibly useful.