I never liked editors like HTMLarea or FCKeditor. The concept is nice, but they often generate pretty ugly HTML code. I could just as well use Word to create web pages. So I tend to use bbcode or markdown syntax, but that isn't exactly easy either.
I just found WYMeditor, it seems to do exactly what I want. It offers an easier way to enter HTML code but still encourages you to use proper paragraph tags and so on.
I need to take a closer look at this, I wonder if there is a Drupal module yet.