Wikipedia is a good example. It is annoying when they ask for the $3 every year, but it's true that a small contribution like that across the many users can keep a free/libre project sustained. Things like Usenet used to be part of your ISP bill anyhow, so a small monthly/annual amount to your instance host makes sense to me. Of course, we pay ridiculous amounts to our ISPs without services like this nowadays, so it does hurt a little
At least you got yourself into the contributing mindset. Tackle the next issue!