An interesting idea that has somewhat intrigued me.
The principal forms of prayer (as recognized by the Catholic church).
Blessing & Adoration
Basically worshiping God.
Petition
Asking God for favors.
Intercession
Asking God for favors on behalf of others.
Thanksgiving
Finally thanking God for all the things we have to be grateful for.
Praise
Telling G. what he/she already knows. See Blessing & Adoration or Thanksgiving.
Meditation
Simply meditating & contemplating God. Perhaps similar to Blessing & Adoration, but I don't think the blessings, our blessings, have any relevance. Simply put it is communion with God, similar in essence to the Buddhists view of meditation....
Now there are only 4 that I remember, yet somehow I have 7 listed. Blessing & Adoration, Praise, & Meditation might be placed all together...