I was just thinking...when I edited a post today and refreshed the page, I saw this:

Last edited by Vorlin on Today at 10:16 AM
Suggestion: how about making the 'on' not show if it's Today or Yesterday? Also, make Today/Yesterday lowercased.

Example (perl):

printf("Last edited by %s%s %s at %s\n",
        $date =~ /[Yy]esterday/ || $date =~ /[Tt]oday/ ? "" : " on",
Just an idea.