Some thing more useful

Such as who and when modify .
I work with many developer man for the same software. So tracking is very important.
Some Control soft software such as CVS or MS visual source safe has its own developer history
and branching ,but I prefer to put history on the source because of more convenient .

For very complex algorithm in low level language such as assembly ,it's hard to
define who is who in the source code .Comment will help the novice developer
to learn the old completed work.

There's some system which is able to extract comment in software into a new text file.
This can be used as an manual or reference sheet of software too.

The comment is not only in software but on any work ,Such as note on the CD,
Attach on the IC, even a sticker on the shelf.

Function or file header is also a comment .

Don't you think that's an important one?