Don't cash out all of it, take a large portion of it and convert it to fiat and use it for whatever you want. I suggest starting a website if you're down to gain more BTC, as it's one of the most profitable. I have ran several BTC-related websites and I would say it's quite profitable. Good luck to your endeavors.
I love that idea mate, but I dont have to cash out all my money or anything . as I have such a big amount I could just easily buy and sell (high vs low) them and use the profits to buy a flat and leave it on rent.
If we was to start a BTC site what do you have in mind. Also what kind of BTC sites have you run before? And which ones did you get the highest and quickest turnover with?