He's using noise on analogue input pin (A0) to generate a random number seed. There is a wire attached to that pin. He's worried that by encasing everything inside a metal box, his numbers will not be so 'random'.
I used a T6963C, They're not the cheapest of displays and require a lot of wiring, but I got one out of a broken MF/HF radio at work, after I built a prototype I ordered new ones from here:http://www.buydisplay.com/default/catalogsearch/result/?cat=&q=T6963C
This is brilliant! Your video is very well presented too :-)I have a load of old pallets which I collect mainly to use as firewood, but it seems a shame. Definitely going to have to borrow your idea, maybe in my bathroom which is due for re-decorating!
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