Love these videos as always! Have you ever considered going into a bit more depth on the hydro stuff? Dinorwig in Snowdonia (the electric mountain) do guided tours and I'm sure they'd appreciate the publicity - plus it's just a fascinating bit of engineering :),(reply>), @Tom Scott how about now?,(reply>), They let Robert Llewellyn in with cameras.,(reply>), Let me know if you want a contact for that Tom, I'll see what I can do ;),(reply>), I've visited Dinorwig, a couple of years ago -- they didn't allow cameras in, and I didn't have enough subscribers to be able to get in. Some other time :)