Constrained Poems

I wrote three poems, each following the same special rule. (The rule just involves the words and their letters, not the poems' rhythm or meaning.)
Figure out the rule, write your own poem obeying the rule, and E-Mail it to me.
I'll post the best submission here.

My first try:

Sets every night, our sun,
    That shines eternal,
    Revolving ever with grandeur and mystery.
In morning it may inspire us.
With daytime's gleaming it brings us healthy sunlight.
Tonight it hides from moonlight,
    But after a beautiful rebirth
    Our sun's unusual journey does continue.

My second try:

Bob looks at Barbie
    Lustily, looks amorously.
``My love isn't kinky,''
    he says, trying a variant more.
Heart flutters, but Barbie
    awaits the words `Marry me,'
``Bob, walk the aisle with me,
    Then divine joy, not before.''

A third try which gives hints:

    Duplicated D.
An unusual rule applies to my poem:
    Cull identical atoms, the word is the home.
Compact stanza now, begin this with D,
    To constitute the headline read.
Try it and you find duplicated,
    Duplicated D.

There are some more poems of this type at the end of this page.

If that was too easy, here's another poem with a different hidden constraint you must discover:

Guess the simple rule operating in this apt poem.
Unlettered fellow will find this coincidental structure hard: Count on it!
Subject doesn't matter; speak of perfected jukebox or approximations,
Or even supercomputers and academic conversations.
Poems wholly without rhymes or meter triumph.
Can you write lawful lines that always follow this constraint?
Contribute your own which obey.
Dearest regards, James Dow Allen (mail address: jamesdowallen at gmail)

More poems of the Sets every night, our sun type

When I posted the puzzle on Usenet, I got an incorrect response to which I answered:

Wrong. Have a hint:
The window's each word,
And the rule is regular.
Composing is annoying
(Maybe not for a juggler).
Although hard, I'm afraid,
To triumph, you ought.
The rule involves
Agreement, adjacent or not.
Highbrow logicians
Don't submit idle chat:
If you HAD found the rule,
You would have known that.

Then I got a correct answer from Ilan Mayer:

That clue
which I've read
made it plain
And availed me
that rule to explain.
Now accordingly
I'll have to show:
This unusual rule
here I know.

To which I responded:

Beautiful and certain.
Hurry you others and
Match Ilan's achieved brain.
Find the poetic knack:
Don't make me post again.
Mr. Mayer solved it!!

Other correct responses included one from Geoff Bailey:

An answer:
Analyse each word;
if it contains two of the same symbol,
make a marginal note.
At the poem's ending,
the symbols you've noted
form not just a watchword
but the first line of the verse.
(Sadly, I am no rhymer.)

Alfred Walters chanced on this page and e-mailed me his solution:

Thanks for the clues
That's a tricky rule! The highlights always help.
Now knowing the way the trekking is easy and won!
Assure I won't divulge the answer, as the effort is quite fun.
Coolness is the guide, errant brittle brains can fail.
Roughhew my poems; No one can ever envy my rhymes, so true!
Accrual of the words and the spelling is a must!
Usually people might resign, but not me I am so close!
Assure I won't give up, until the rule is done.

Here is a motion-gif puzzle I stole off the 'Net:

Is this 12 men or 13 men?