As an alternative to the insurance included with certain credit cards...

Some years ago, I had found a site online to buy separate car rental insurance coverage. It wasn't packaged with other travel insurance, just the car rental insurance. As I remember, it was much cheaper than paying the daily rates from the car rental companies. Does this option still exist? I didn't use the site for a couple of years and now I can't find it again.

Thanks!


P.S.: I've heard about the insurance from AmEx in the USA, but I do not have that card. The insurance I mentioned above was not dependent on any particular credit card.