"A Monetary Valuation of Individual Religious Behavior: The Case of Prayer "

That's the title of a paper in the April 2012 edition of Applied Economics.
Improbable Research has the story:

Putting a Price on Prayer

•Some people might feel happier if they get their hands on some more money.
• Some people might feel happier if they use their hands to pray.
Leading some to the question : is it feasible to equate the two? In other words, is it possible to put a price on prayer?

Timothy T. Brown, Ph.D. (Assistant Adjunct Professor, Health Policy & Management Associate Director for Research, at the Berkeley Center for Health Technology) has entertained just such an idea. And has a paper scheduled to appear in the journal Applied Economics, Volume 45, Issue 15, 2013. The article : A Monetary Valuation of Individual Religious Behavior: The Case of Prayer is currently available (to non-subscribers) for $36.00.
It found that :
“Praying at the frequency of the national mean of 8.1 prayer sessions weekly is valued at $53,055 (2004 dollars) per annum.”...

Also at Improbable Research:

Richard Feynman and the word “muggles”

Deciding not to blow up a cow (officially)