I have a good friend that does house sitting for their friends and family.  Specifically house sitting for people with pets.  It can cost around $60 a day to keep a couple of dogs in a kennel while you go on holiday.  There is also the time you need to take and pick up your pets while you should be busy getting ready for your holiday or business trip.

People are also happy just to have someone in their house while they are away for security.  The dogs are happy too as they can stay in their familiar environment.  My friend gets some execise taking them for walks while getting paid.

My friend works as a "remote executive assistant", so as long as the house has an internet connection, they can do that job as well as looking after looking after people's houses and pets.  

It's a win-win situation for everyone involved and my friend can effectively earn two incomes at the same time.  Obviously people will only trust friends close to them to stay in their house, but I am sure once you start telling people about your service, you will eventually have to start taking bookings in advance for your work!