I use my bitcoins to do some trading on weekends and investing in ICO which I find worth investing.
I also usually buy goods online with bitcoins.
Spending bitcoins in ICO is very useful and profitable, I spend my bitcoins in Initial Coin Offering of ICONOMI and now I am waiting for that to put in the exchange Market. And I also spend my coins in buying books and articles online, one thing more I use my coins for buying clothes online.
That is a good investment to make at a moment and it has good reputation and I am sure you will be making good profits from it once it gets listed on exchange sites.