I don't think there's been a thread about this yet, so I'll give it some publicity on TSR!
Richard Wiseman is the Professor of the Public Understanding of Psychology at the University of Hertfordshire, and he's conducting a mass experiment between the 3rd and 7th of August.
Basically, there are small practices and behaviour that have been claimed to have the effect of making people happier in general if they carry them out.
So what do you have to do? Not much. Go to this site:
Read the instructions, fill out a small questionnaire which has only 7 questions (takes less than a minute), provide your e-mail address, and then watch the video in which Richard explains which technique he'd like you to perform over the 5 day period next week!
They will send you an email on the first day to remind you, and at the end, they'll send another questionnaire just to see how effective it was.
I'm not sure if talking about what technique you got would skew the results, but mine was to take 5 minutes each day and just think about something for which you are truly grateful - your new car, your life, your degree, your family, your friends, your relationship, your home, your kids, your xbox, whatever!
So, do the experiment, and not only will you be helping out science, you'll also be making yourself, and the world, a happier place (hopefully!).
Also, Richard Wiseman is one of my favourite authors of psychology, so I thoroughly recommend his books too.
Find out how you've done here