Good answer from Ian Patterson on Quora:

This is an older topic, but I've seen enough recent questions along the same lines that I think its good to outline what options exist today. If you look beyond DISPLAY ADVERTISING, which I believe the intent of the question is, there are a number of options to consider in monetizing your website:

Shameless self promotion:

• Sell anonymous data: Your website can easily become a passive revenue stream, without annoying ads. Your visitors produce anonymous data that can be resold. http://www.fuse-data.com  can help make that happen. 

Asking your visitors to do something:

• Donations: Asking for donations to help support the site, either through PayPal or similar, has been around for many years. Newer, more structured ways of getting users to contribute can be found in Patreon: Support the creators you love
• Surveys: Alec mentioned http://survata.com  is mentioned in this thread, which is one way of asking your users to 
• CAPTCHAs: If you have a website where it makes sense to use a captcha, you can get paid every time your user completes a captcha using a service like  http://solvemedia.com/

Having others sell products

• Affiliate Links: This is where you link to a product on another website (such as Amazon or eBay), and if the visitor buys that product, you get a percentage for having referred the visitor to the site.
• Display Advertising: Adsense is the largest ad network, but as others have mentioned, there are many alternatives you can use. 
• Sponsored Posts: Common in the travel industry, you can accept money from others looking to post on your website, provided you properly disclose that the post is a "sponsored" post. 

Selling your products

• Digital/Information Products: Creating an eBook, Paid Report, or similar information/digital product is a way to create a product that you can sell to your users.
• Physical Products: You can sell physical products, either by accepting payment and shipping them yourself, or using a fulfillment service like Fulfilled by Amazon or a dropshipping company to handle the shipping and delivery of your products.
• Premium (paid) content: Similar to a digital product, you can section off a part of your website that has "premium" content, which users need to pay and login to view.
• Subscription Services: If you have a service you can offer, you can charge a subscription fee to use this service. 

Hope this helps!

Disclosure: I run http://www.fuse-data.com which helps monetize websites

Are ads a poor way to monetize websites?

https://quora.com/Are-ads-becoming-a-poor-way-to-monetize-websites

Short answer: Yes.

On monetizing a website with 11 million users:

https://quora.com/How-do-I-monetize-a-website-with-11-million-unique-visitors-per-month

Not many websites have more than a million visitors:

https://quora.com/How-many-websites-have-more-than-1-million-monthly-unique-visitors

How to monetize 30,000 monthly uniques:

https://quora.com/How-should-we-monetize-now-that-weve-reached-30-000-unique-monthly-visitors