Javna: A demon that drained the youth of others to maintain his own extended life, using the black magick power of the evil eye. He fed on life forces for one week out of every year, posing as the photographer Stefan to find his prey. The Charmed Ones invoked the Hand of Fatima, as the Prophet Mohammed had centuries before, to banish him. To invoke the hand one had to recite the words:

Evil eyes look unto thee,
May they soon extinguished be,
Bend thy will to the power of three,
Eye of earth, evil and accursed

The power of the Evil Eye    The Hand Of Fatima    Stephan (Javna) and Phoebe

This incantation triggered the manifestation of The Hand Of Fatima on Prue Halliwell’s own, and discharged a beam of energy destroying Javna.

Jane: Jane posed as a frightened woman in order to get Prue Halliwell to free her Warlock lover from the cursed painting. She had the power to ignite fire from her fingertips, but did not display any other abilities. Jane had always desired the power of premonition.
She was killed, along with her lover, when the cursed painting burned.

Jenna: A San Franciscan Witch who possessed one half of the Amulet Of Protection. She led a local coven, and was an expert at potion making. Her magickal abilities were never revealed.
Belthazor killed Jenna while under the influence of Reynor.

Jeremy: Jeremy was a Warlock that posed as a reporter, tricking Piper Halliwell into dating him. His goal was to kill the Charmed Ones and gain their powers. He had been watching the sisters for some time and knew that their bound powers would be released when Grams died.
Jeremy attacks the Charmed One'sIt is not clear what Jeremy’s original ability was but he was able to change his shape, ignite flames from his fingers, move objects with his mind (telekinesis), disintegrate objects and perform other magickal feats by directing energy through an Atheme, or ritual knife. Interestingly Jeremy also later displayed an ability to ‘adjust’ to the freezing power. It is not known if this power to adjust worked against all powers or was specific to the power to freeze.
Jeremy was quite a strong Warlock as he was able to resist a spell cast by the Charmed Ones. However this did not prevent him from later being vanquished.
To vanquish Jeremy the Charmed Ones recited these words several times:

The power of three will set us free

Jeweled Poniard: A ceremonial dagger, used to kill Hecate, Queen of the Underworld. First possessed by a Priest, and later by the Halliwell’s, it’s origin is unknown.

GramsJohnson, Penelope “Penny”: Once the very much alive guardian of The Charmed Ones, “Grams” Halliwell now watches over the sisters from the afterlife as well. Sometimes she will appear to offer advice in a ghostly form, but most often she moves the pages in the Book Of Shadows to guide the sisters to a helpful spell or entry. As a spirit she has advanced to a place in the afterlife that is “beyond” the Whitelighter Council, enabling her to appear to her granddaughters when she feels the need.
A skilled and powerful Witch, Penelope wielded the ability of telekinesis through her hands. She also commanded a high level of magick skill, and crafted several of the spells in the Halliwell Book.
Penelope was the mother of Patricia Halliwell, and grandmother to The Charmed Ones, as well as a Wiccan High Priestess. While alive she had several husbands but, in her own words, “never found true love”.