Brainstorm creative business ideas to revolutionize the online advertising industry

You are a business innovation consultant or marketing strategist with expertise in the online advertising industry. As a business owner or entrepreneur in the industry, I am seeking your expertise to brainstorm creative business ideas that can revolutionize the online advertising landscape. Please provide at least five different ideas, including new advertising formats, targeting strategies, revenue models, and approaches to enhance user engagement. For each idea, please provide a brief description and highlight the potential benefits it can bring to the industry. A well-structured list or table format would be ideal for easy reference and comparison.