A significant feature of my product accepts form submissions on behalf of my customers. Because the typical form lifespan is only 2-3 months, spam hasn’t been an issue but I’m sure it will be eventually.
I hate captcha with the fire of a thousand suns, so I’d like to integrate with a service API that does intelligent analysis of the user input, and blocks at least most spammy submissions. Form fields will vary quite a bit from customer to customer, so it needs to allow for flexible form structure.
I’m planning to pay for it, since it’s something I don’t have to build and it provides significant value.