HOSTS files... various sources around, pick and choose ones that suit & you will block a lot of ads & popups, etc
Agree with Saracen there, not all of us have unlimited and/or high bandwidth. And even if we do, we dont want this junk thrown in our face.
Have had to use a mobile dongle recently (limited Gigabytes) whilst travelling and it really brings it home how large some pages and their garbage can be!