What skills are most crucial for running small internet companies?
Marketing and sales.As awful as that sounds to many people it just isn't enough to build an amazing product, write great code, or design something beautiful. You need to be able to get out there and tell people it exists in order to succeed. Without that ability your startup will fail. In fact, in my experience at least, far more companies fail because they couldn't reach customers than fail because they couldn't build something. Building something is the easy bit.