One of the most beautiful and exciting qualities about blogging is that you can create a blog that deals with any subject area that you are either knowledgeable or passionate about (and preferably both!). You can write about personal finance, careers, real estate, getting into business, technology, cooking, travel, personal health, or just about any topic you choose.
While these models have diminished in mature e-commerce and online advertising markets they are still prevalent in some more nascent industries. China is one example where Affiliate Marketing does not overtly resemble the same model in the West. With many affiliates being paid a flat "Cost Per Day" with some networks offering Cost Per Click or CPM.
Like Airbnb, becoming a ridesharing driver for companies like Uber, Lyft or Sidecar is a way to join the shared economy. And though it is not technically earning money from home,  it allows the same kind of flexibility and it is a way to use an asset you already own (i.e. your car) to make money. There are things to keep in mind, though, about driving other people such as whether your car insurance will cover you and how you pay taxes on your earnings.