Du' al-Iftitah was taught by the Imam Mahdi (ajtfs) to recite every night during the month Ramadhan. The Du'a is excellent for molding man's attitude towards his Creator, as it discusses many aspects of the wretchedness of the human being, and the grace of Allah (swt).
The Dua can be divided into two parts: 1) Man's relationship with Allah and 2) Divine leaders.
http://www.duas.org/iftitah.htm