All I can think of is write a book, write software or design a website - all can be done from home. Or operate a mail order business and keep your stock at home etc.. a more modern version might be ebay shops.... Richard branson started making his big money when he operated a mail order records business. It eventually became the Virgin music label we know today.
I'm not sure what the 'work from home' idea means because any office can be moved to the home. YOu can get a job with the likes of IBM and work from home with a laptop maybe 1 or 2 days a week. I often see adverts for 'working from home' as if it means no effort and no skill. I am sure theres not many ways to make money with little effort or without huge risk.