Online collectors' baseball card auction. Instant automobile insurance broker. These ideas are free. Take 'em, they're yours. You may already be working on something like this in your spare time.
Ideas are everywhere.
Step carefully, or another opportunity will go off right in your face. Most likely your competition will come from small companies you've never even heard of. They're not in your business. They're not even trying to be rivals. But they will be, because they are taking the initiative to try something new, taking traffic away from your site and taking customers away from your trough.