Advice: how to monetize a website with – 30,000 page views per month?

I have a technical website with ~ 30,000 page views per month --- how to monetize this?

(the site is a how-to-do-various-useful-things-in-programming-language-X sort of site)

I tried putting a "donate using bitcoin" badge on there but guess what: total BTC donations so far are 0.000

I don't want to put ads up (unless someone tells me I can make considerable $$ doing so and even then it rubs me the wrong way)

any other suggestions?