Amla Cool Oil (you can get it on amazon). Heat it up a bit (I place a ceramic mug in a boiling pot of water for a minute or so), rub it on your scalp, put on a baggie and even a heat cap. You can also inhale deeply and it will open up your sinuses if you have a cold. I seem to feel the benefits more on damp scalp, so try spritzing scalp with water first. I would plan on shampooing it out afterwards though. It is very smelly, and that says a lot for me to say that because I love herbal smells.
It is VERY strong though. I think it's one of the strongest.
Balsam Paprika hair Mask: Also on amazon. Put it on, put on a plastic cap, wait for 10 minutes and then you will FEEL IT. I'd definitely do a spot check first, you don't want to cause any irritations.
This is a similar burn to the paprika masque, but I didn't find it quite as strong - not to say it isn't strong at all. Definitely do a patch test.
And of course, LHDC (Long Hair Don't Care) on Etsy. This is a cowash, it's nice and tingly and I use it almost every day in the summer.
I felt like I'd have more oils on this list, but I'm drawing a blank.