How often do we think about money?
There is a dearth of research on this subject but I suspect the answer is 'more than sex' (which is 19-times a day for men and 10 for women, according to a recent pseudo-scientific poll).
After an in-depth 10-minute search of the internet the best I could come up with was a 2008 research paper titled 'Merely Activating the Concept of Money Changes Personal and Interpersonal Behavior'.
The findings, based on a number of laboratory experiments, were two-handed: On the one hand, participants reminded of money were less helpful than were participants not reminded of money, and they also preferred solitary activities and less physical intimacy, the study says.
On the other hand, reminders of money prompted participants to work harder on challenging tasks and led to desires to take on more work as compared to participants not reminded of money.