TLDR: Each point is worth about 0.012¢ - 0.109¢ ($0.00012 - $0.00109) depending on what you want and how many you have. The more you have, the more they're worth, but what you get also makes a big difference.
I just noticed that verizon has a rewards program, and so I spent a few minutes trying to work out approximately how much my accrued 74,710 points were worth. There are a few different ways to spend the points, but the gift card auctions seemed like one of the most straightforward ways of getting a real-world value. Helpfully, verizon will show you all past auctions on a single (huge) page, and they even include a copy of jQuery for easy data scraping!
Here's a quick one-liner that you can paste into the console to reduce the page to a single chunk of JSON (