When most people create a comment (Review Tab, New Comment, or Shift/F2), [Excel2003:Insert|Comment], they accept the shape and color and just enter the information they want. So most comments look something like this:
But how about a comment like this?
Or even this: (It's me!)
Here's how you can do it:
When you first create a comment, the cursor is right after whatever you typed. You need to select the comment itself, not the text inside. So, select the border of the comment.
You need the "Change Shape" tool. This can be placed on the Quick Access toolbar: [Excel 2003: View|Toolbars| Drawing|Draw Menu|Change AutoShape]
When the comment is selected by the border, click the new Change Shape tool.
From that, you can select basic shapes, block arrows, flowcharts, stars and banners, or callouts, each of which has yet another set of shapes to choose from. Shown here is the Cloud callout:
Once you have the new shape, (cloud, here), right-click the border once again, and choose Format comment as shown, if you wish to format this comment even further:
That will bring up yet another dialog, from which you can choose Fill Effects:
From this dialog box you can select the Picture tab and import any picture (I chose me!).
As you saw before.