Once the CyanogenMod team found and implemented the hidden Heads Up notification mode, it was basically inevitable that all the other major custom ROMs would follow suit. The unicorn-powered Android Open Kang Project has done so with their first nightly based on Android 4.4.4. They've also thrown in the usual bug fixes, as well as settings for automatic Immersive mode, disabling the full-screen keyboard, lockscreen orientation, and a few other goodies.
But the best news, at least for owners of a few select devices, is expanded hardware support. Today's nightly build is being published for the first time for the LTE version of the Nexus 7 2013, the international Galaxy S4 Mini LTE (GT-I9195), and Oppo's high-powered Find 7a. The Nexus 7 LTE is probably the biggest addition, since it's the one with the highest number of likely ROM enthusiast owners. That being said, remember that the nightly builds are likely to contain bugs, especially for new devices, and especially for fresh releases of Android.
If none of that deters you, head over to AOKP, find your device, and grab the latest build. The Android 4.4 Gapps package containing the Play Store and other Google-branded services can be found here - the popular CyanogenMod version may not work with AOKP.
Source: AOKP Blog