You can kill yourself with a 9 V battery … or things I learnt this week

1. You can kill yourself with a 9 V battery,  the ‘real’ story of an unfortunate American sailor. This is surprising and I didn’t knew this earlier. I used to put the 9 V battery on my tongue to feel the current. Found the link from a Slashdot discussion in At Oxford, a Battery That's Lasted 175 Years.
2. Taking notes on a laptop is less efficient than writing with pen on paper. It is, in fact, detrimental to learning!  This has to do with the speed at which writing notes using a pen and a laptop differs. Writing long hand is slow and will force the note taker to summarise the information he is receiving; laptop note takers often copy sections verbatim from the source, which requires less thinking. ‘I had the sense that their brains were less engaged and that they were acting more like stenographers than students.’
3. On Winston Churchill’s ninetieth birthday thousands of greeting cards were sent, addressed to ‘The Greatest Man in the World, London’, and they were all delivered to Churchill’s home.