My dad has a five-year-old 42" plasma TV which, in my opinion, is still excellent. He has seen the adverts for Smart TVs and was considering buying a 42"-50" LED Smart TV for around £900-£1000 but after realizing how little he could sell the current plasma TV for (around £100-£200), I advised him not to sell it. Instead, I offered to research boxes to make his TV into a Smart TV (or close to). He already has a Sky HD box. What exists? Any suggestions?