Amabile, Teresa M. "How to Kill Creativity." Harvard business review 76.5 (1998): 76.
Art experts judged the creativity of artists' work without knowing which works were done on commission. While the artworks were similar in technical quality, the work not done on commission was startlingly more creative.
Ariely, Dan, et al. "Large Stakes and Big Mistakes." Review of economic studies 76 (2009): 451-69. Dan Ariely website. 4/6/2011 <http://danariely.com/the-research>.
This study showed that financial bonuses were effective in increasing the performance of mechanical tasks, but decreased performance for even the most rudimentary cognitive tasks.
Grant, Adam M., et al. "Impact and the Art of Motivation Maintenance: The Effects of Contact with Beneficiaries on Persistence Behavior." Organizational behavior and human decision processes 103.1 (2007): 53-67.
University call-center fundraisers doubled the number of pledges and amount pledged after finding out how thier fundraising benefits the recipients of scholarships.
"The HBR List: Breakthrough Ideas for 2010." Harvard business review 88.1,2 (2010).
Presents a short summary of the study in which people were electronically asked to record what they were doing, how they felt, and how motivated they were at that moment. Found that making progress in the work was the highest motivator.