Patikulamanasikara

Also called Asubha (not beautiful and neutral) meditation. I think it's the most mentioned meditation in the Pali Canon. 

"Just as if a sack with openings at both ends were full of various kinds of grain – wheat, rice, mung beans, kidney beans, sesame seeds, husked rice – and a man with good eyesight, pouring it out, were to reflect, 'This is wheat. This is rice. These are mung beans. These are kidney beans. These are sesame seeds. This is husked rice'; in the same way, the monk reflects on this very body from the soles of the feet on up, from the crown of the head on down, surrounded by skin and full of various kinds of unclean things [as identified in the above enumeration of bodily organs and fluids]" (Wikipedia)

The parts of the body according to 2500 years ago (32 parts): head hairs (Pali: kesā), body hairs (lomā), nails (nakhā), teeth (dantā), skin (taco), flesh (maṃsaṃ), tendons (nahāru), bones (aṭṭhi), bone marrow (aṭṭhimiñjaṃ), kidneys (vakkaṃ), heart (hadayaṃ), liver (yakanaṃ), pleura (kilomakaṃ), spleen (pihakaṃ), lungs (papphāsaṃ), entrails (antaṃ), mesentery (antaguṇaṃ), undigested food (udariyaṃ), feces (karīsaṃ), bile (pittaṃ), phlegm (semhaṃ), pus (pubbo), blood (lohitaṃ), sweat (sedo), fat (medo), tears (assu), skin-oil (vasā), saliva (kheḷo), mucus (siṅghānikā), fluid in the joints (lasikā), urine (muttaṃ).

It's not quite a body scan, and it's not quite a 6 elements meditation. "In addition to developing sati (mindfulness) and samādhi (concentration), this form of meditation is considered conducive to overcoming desire and lust." (op cit)

It supposedly conquers lust, and I'm skeptical, and I've had a few lustful meditations, so I'm going to try it, and report back. I don't like the language of "impurity" either, misses out the wisdom of equality. Honestly I think everything my body I am grateful for. The calling it of ugly rubs me the wrong way. Maybe that's my conditioning. Maybe I could recognize my conditioning around the attractiveness of the body. 

I once did a meditation at the Bodies exhibit at South Street Seaport, where Chinese prisoners donated their bodies that were rubberized and cut in all sorts of interesting ways so you could see inside. You don't really need to do the corpse meditation too many times, once might be enough, but doing it once is perhaps good. Most people don't have charnel grounds to go to, so the Bodies Exhibit was the best approximation.

It's about bringing balance.

Links:

Written meditation instructions.

Lead through on YouTube (BuddhaDhamma Foundation) by Ajahn Asoko. He meditates, then talks about the meditation before it begins at 25 to talk about the meditation, prior to that he does a little meditation. Supposedly Ajahn Chah would do a walking meditation where you can put a bit down when you turn, and then when you get back put another part down, and then all these parts of the body are scattered all over the ground. All that goop is yucky. Then Ajahn Chah suggests you put it all back together. 1:05:00 begins questions. Do you have to keep the order of the list? Probably best, but of course you are free to do what you want. It's a really good suggestion to do this in walking meditation, I've been wanting to juice up and refresh my walking meditation. 

Chant

8 page pamphlet on Asubha meditation.

(The above is a goddess of fruitfulness and fecundity, from early Buddhist times in India at a recent exhibit at the Metropolitan Museum of Art in NYC.)