Yesterday was Pi Day, and what better way to celebrate everyone's favourite mathematical constant than by taking a look back at everyone's favourite cheap hobbyist computer, the Raspberry Pi. Since the launch of the Raspberry Pi, I've written an absurd number of guides, blogs and an already outdated book on the variety of projects you can do with it. I've learned a lot it that time.

Dear Lifehacker, my 15-year old son is bugging me to buy him a PlayStation 4 Pro console for his birthday - he's even willing to put half the money towards it. The thing is, he already owns a PlayStation 4 which still works fine. Is this upgrade necessary to play future PlayStation games or will it just be a waste of money?

If you're thinking of giving someone an Xbox, PlayStation, Wii U, 3DS, Vita, or iPad this Christmas, there's something you can do to sweeten the deal even more for the recipient: download every update for the console first.