A prayer by St. Francis of Assisi that I found very moving:
Most high, all powerful, all good Lord! All praise is yours, all glory, all honor, and all blessing. To you, alone, Most High, do they belong. No mortal lips are worthy to pronounce your name.
Be praised, my Lord, through all your creatures, especially through my lord Brother Sun, who brings the day; and you give light through him. And he is beautiful and radiant in all his splendor! Of you, Most High, he bears the likeness.
Be praised, my Lord, through Sister Moon and the stars; in the heavens you have made them, precious and beautiful.
More at the source.