not necessarily SaaS products, but I'm thinking of software for professionals:<p>- software for lawyers, accountants<p>- software for the health industry<p>- graphic software such as photoshop, 3DSMax or Final Cut pro<p>the overall market is smaller, but you can sell the software for more. Also might need a little bit more topical knowledge, but imho it's the same quantity of work as doing a Microsoft Office clone<p>another market with fat margins is MMO video games. I'm sure there are lots of niche markets out there wanting their own game