Man, I remember having a dream that I had been gifted (or accidentally given) four bitcoin and it caused me to panic about my security setup. I'm sure the first thing I'd spend my time on is a storage situation I was comfortable with for that quantity.

With that taken care of, we'd move to our ideal location and go full heatpunk with the home heating. I would probably evangelize my new neighbors to do the same and help them get set up.

I'd approach the local merchants offering to pay them a significant lump sum amount to start accepting bitcoin (and heating by mining).

With the rest, I think I would do some combination of investing in and starting bitcoin businesses. Even those 50 BTC probably aren't enough to buy the very failed The Economist, after all, so I need MOAR if I'm going to make @denlillaapan's dream come true.