Depends how much risk you are prepared to take. If you want to play safe, Bitcoin, Ethereum and Litecoin are your friends. But don't expect to get rich in a few weeks.
If you feel lucky and don't want to miss opportunity with growing coins, you can try DeepOnion (has been growing consistently for the last 3 weeks) and YOYOW (new Chinese blog that pays for good content, similar to Steem).