Sakhmet

Her image is a woman's body, with the head of a lioness, usually crowned with a solar disk with a cobra wrapped around it (a uraeus).

She is the called the eye of Re, and she personifies the fierce and withering aspect of the sun. She is also sometimes called Nesert, the flame.

When Re used Hathor as an instrument of vengeance against the wicked, she became Sakhmet, and very nearly destroyed all of humanity. In Memphis, where her cult was strongest, fear of a repeat performance was so strong that her priests erected over 700 statues of her, and adhered to a strict regimen of propitiation. They conducted rituals at two statues a day, every day. Better safe than sorry.

Her kind of power was very useful for battle, and she was the defender and champion of the pharohs in warfare. Unfortunately, her hot breath could also dispense pestilence and disease. Her mastery of these elements could cut both ways, so in later times, most of her priests were also doctors.

Another feline goddess, Bast (or Bastet), was closely associated with Sakhmet (and with Hathor, as well). Bast was the domesticated kitty to Sakhmet's lioness, and they eventually came to be paired, with Sakhmet being the guardian of the West, and Bast the watcher of the East.

Most of this information is from:
http://www.redrival.com/elisabat/sekhmet.html
http://www.egyptianmyths.com/sekhmet.htm
http://www.per-bast.org/