Ugh, what's with the "evolutionary vestige" and "instinctual idleness" crap? The lead researcher is a behavioral psychologist, not an evolutionary biologist. There's no basis for the conclusion that this behavior is genetic, let alone instinctive.

This makes perfect intuitive sense to me and is reflected frequently in my life. I have a job where I can often get away with doing very little, but if I do that I feel bad (and it creates a negative spiral). If instead I engage and work hard, I feel much better, but it seems I am always batting a innate preference for inaction. Or just laziness :-)

I like the chocolate bar experiment. Even if the rewards were switched, more people would still opt for the "busy" option. That has very interesting implications: At times, the reward really doesn't matter. It's the process which is important.

Implications for user interface design?

Complicated user interface + no reward: "majority (68 per cent) of students chose the lazy option" == the majority of people will simply hit the back button in their browsers.

Complicated user interface + reward: "majority (59 per cent) chose the [...] 'busy' option" == the majority of people will use a complicated interface, if there is (social or other type of) reward.

Hmm.. I can think of one off the top of my head. Give the user something to do or read while he is waiting for content to load

Google has made this a lab option in gmail called 'gmail preview' if shows a quick snapshot of your email while loading ... pretty cool

Ask a user for his e-mail address (newsletter subscription) while he is waiting for a download. This works well for me.