There are sites that you can loan out your coins to other users for set periods of time, and at the end of that time frame they return it to you with a specified amount of interest.  I know GDAX was doing this for a while until the ETH price crash a few months ago.  I assume other exchanges offer the same service if you do some research.  Basically risk free, beyond keeping it on an exchange. 

Other options would be to transfer to a POS token like what ETH will be and then stake your tokens.  This option does come with increased volatility however.

Best of luck