CyanogenMod has made a reputation for supporting smartphones and other Android devices well beyond the point in which their manufacturers would. Many users that are outside of their warranty period, but not ready to give up their smartphones, will turn to CyanogenMod and flash their ROM onto their smartphone to have the latest version of Android, and in many cases, having a more secure smartphone, as these now come with security patches straight from Google. CyanogenMod is built off of AOSP, so you're getting the barebones of Android, along with a few features that CyanogenMod has built in over the years.
Now it appears that a number of devices are getting updates to CyanogenMod 13 - which is based off of Android 6.0 Marshmallow - which include both nightlies and more stable versions as well. These devices, some are older than others, are not very popular, except for maybe the HTC One M7. But the devices currently receiving updates are the HTC One M7, Wileyfox Spark, Wileyfox Spark X, Aquarius X5 and the Aquarius E5 4G. If you own any of these devices and wish to flash some CyanogenMod 13 goodness onto your smartphone, be sure to hit up the source link below. The HTC One M7, Aquarius X5 and Aquarius E5 4G are all getting the bump from CyanogenMod 12.1 to CyanogenMod 13. Essentially going from Lollipop to Marshmallow. While the Wileyfox Spark and Spark X are getting their first custom ROM tastes here. Since these two launched with Cyanogen OS, which has now been killed off in favor of a modular OS.
Keep in mind here that you will need to root your device to flash CyanogenMod 13. So make sure that you are no longer under warranty, as rooting your device will indeed void that warranty. So if anything should happen, you are essentially on your own here. You will also need to download and flash the latest Gapps zip, otherwise you won't have any Google apps installed on your device, nor any Google Services. As CyanogenMod and other ROM developers, are unable to bundle Google Apps into their custom ROMs, which is a bit unfortunate, but it's an easy fix.