The always fascinating Cool Things in Random Places hosts an article on the Karni Mata Temple in Rajastan, India, based in turn on a feature in National Geographic. Devotees flock from all over to worship and feed the temple’s 20,000 rats, paying their respects to Mother Karni, a 15th-century mystic.
From the official Karni Mata site (lowercased from the all-block-letter original to protect your retinas):
According to the folklore, Shri Karni-Mata once restored a dead child of her devotee back to life from Yama (the god of death). Then Mata announced that no one from her tribe would fall into Yama’s hands again. Instead, when they died all of them would temporarily inhabit the body of a rat (Kaba) before being reborn into the tribe.
A normal human being will be absolutely scared over the thought of the number of rats (they look like rats but actually are not rats) that exist but the outstanding fact is that these Kabas are harmless and play around in the temple without disturbing the devotees[.] Rather, they sit on their laps, shoulders, head, hands, which the devotees think to be the divine spirit and blessings of the goddess.
[...] When the killed disease plague spread out in Surat (Gujrat) in the mid-90′s, people from Surat and other affected areas went to the temple to take the milk and water drunk by these rats as medicines to get themselves cured.
Apparently, the rats never leave the temple and have never caused problems for the surrounding town. Adding to their mystique is the fact that they seem to be reproducing and raising their young exclusively in some secret underground nursery — all the rats in the temple are fully-grown adults.
National Geographic reports that “[t]he veneration is so complete that if someone accidentally steps on a rat and kills it, they are expected to buy a gold or silver rat and place it in the temple as atonement.” Shoes are forbidden, and if a rat scurries across over your bare feet on a visit, it’s considered a sign of good luck.