You won't believe 90% of my pages are built that way (out of ignorance), and it is only recently that I have started implementing the "one line" meta tag!

Another simple yet effective post! I think in some of your examples, you could make the code slightly more efficient i.e. reduce the code to content ratio, which is better for search engine rankings.

For example, you gave:
<meta name="ROBOTS" content="noindex">
<meta name="ROBOTS" content="nofollow">

But this can actually be:
<meta name="ROBOTS" content="noindex,nofollow">

Not forgetting a forward slash before the closing bracket if you code in XHTML of course

It is good to be reminded of some of the page tweaks from time to time though - it's so easy to get hung up on the content and forget about how your site appears in the search engines.

Thanks,
Emma