I tried a meditation exercise from Jason Miller's book strategic sorcery tonight. Actually, I liked it the first time so I did it again a couple hours later.
The effect were awesome. I could feel how one side of my body registered atavistic energy and how the other side blocked it. Then I felt that other side allow the movement of the Cthonic. Awesome. I've been a lot more sensitive to energy of late but this was very very specific.
Several hours later, I'm still buzzing and awake. I should have been asleep two hours ago.