archive.is/archive.ph the one mentioned in the main post and one that is most effective out of all the options
12ft Ladder - What I like about 12ft.io is that once it gets rid of the paywall, it makes sure the website stays as the mobile site (if you're using your phone), whilst archive.ph uses the desktop form by default. However, 12ft.io does not work as well as archive.ph
Remove Paywall - Even more limited than 12ft.io, but it's another alternative. As the site says, make sure to add RemovePaywall.com/ ahead of the URL if you want to copy the unpaywalled link.
Chip - The most limited option out of all four, I think. Another disadvantage is that I don't think you can copy the unpaywalled version's link, unlike the others.
You copy the URL to the paywalled article, paste it in archive. In most cases, someone else has already archived it already and it's ready to view.
I also use Bypass Paywalls for Firefox in the browser, this takes care of less intrusive paywalls - for the big boys (big news orgs) the archive.is solution is the best.