I entered code into a HTML gadget to add Comments RSS Feed to my Sidebar.
After reading the following website info, I was able to create this by copying the code in my gadget for Posts (RSS) and just changing the word "posts" to "comments" in the code of my new gadget.
I subscribed myself and it works OK.
However, I should mention that when I was at the dialog box to subscribe, it just showed the name of my blog, so I added "- Comments" .
At the moment there are only 2 comments - one comment made by my Professor and my reply comment. I deleted my test comments to avoid unnecessary clutter.
I just thought this feature might become useful as time passes.