There absolutely is still room for new affiliates, because there are always new products to promote and new audiences to reach. The internet is a vast place with infinite verticals to work in, so instead of just focusing on the biggest affiliate programs in a specific industry I recommend using that one as well as others (and Amazon!) to round out your affiliate offers and thus your revenue.
If you're looking to address some immediate financial needs, then the app economy is likely right for you. Thanks to the global sharing phenomenon, launched in part by our smartphones and ever-burgeoning global connectivity, you could easily opt for some quick active income by using well-known apps. From ride sharing to deliveries and even quick tasks, there's an app for that today, as the saying goes.
Whether it’s an important consumer application, a specialist app to solve a particular niche problem, or even a time-wasting game you can play on your phone, you can create a massively successful business if you build software that helps people. (Look at the rise of Slack—the team communication software that went from side project to billion-dollar company in just 2 years.)
Mechanical Turk is Amazon's take on micro-jobs. These are small miniscule-jobs that you can do for other people, which they call HITs, or Human Intelligence Tasks. These are super simple tasks that anyone can do. Some examples are listing off some URLs with certain kinds of images for one cent, or recording a few phrases with a microphone for 6 cents.
Sites like Share-A-Sale and Amplifinity provide referral fees. Vendors set the referral fees they're willing to pay and for what services. When the transaction happens, you get paid by the company for introducing a new customer to them. uRefer also allows merchants to set up referral programs for introductions and meetings, in addition to any transactions made.
Money can be earned and spent, saved and pilfered, invested and wasted. Not time. That's why time is far more valuable than money. The point? When you lack the luxury of time, making money online (or offline) can seem like an impossible task. How are you supposed to do that when you're working at a life-sucking nine-to-five job? While the stability of full-time employment might allow most to sleep well at night, it doesn't empower your creative juices to search for new income-producing strategies.
If you have pop-ups and optins on every page, I would have to think that it would be a lot harder to convince someone to link to it. Especially since the pages where you have your optins (and probably receive the most traffic) are probably the same pages that you have your best content on as well that you'd be hoping to pitch in your outreach campaign.