i'm also interested in the "chakras" but i haven't really done specific practices pertaining to it. my only experience, which is close to the chakra model, was a sensation of energy/waves rising up to the top of my head (as if pulling my hair), while doing lying down meditation.
here's a ton of information on it: http://www.kheper.net/topics/chakras/
also, Wilber takes the subtle energy theory to a whole new level. see "Toward A Comprehensive Theory of Subtle Energies"
http://wilber.shambhala.com/html/books/kosmos/excerptG/part1.cfm
would love to hear Kenneth's take, especially on Wilber's geeky theory on subtle energies.
~C
P.S. Alex Grey is one of my favorite artists. i have a copy of Sacred Mirrors on my coffee table. very powerful images. but i don't resonate with his use of psychedelics (see http://bit.ly/14Qm2 ) - a good topic for discussion for another day. to each his own i guess