Sometimes its hard to find good data source when you make some side projects especially when you want to use survey data. I found an interesting site called data.world. There are more than thousand database freely available after registration.
It has a cool feature: you can export the data directly to R, so you do not need to download it to your local drive.
However sometimes it is tricky to use this function because the file format is not always .csv as it assumes, but of course you can use the link of the data source in this case.