In honor of National Cat Day, on-demand car service Uber became an on-demand cat service, delivering kittens for 15-minute snuggle sessions.

On Oct. 29, the Uber app featured a "Kittens!" request button, and for a $20 fee, a car brought a shelter kitty to your door along with cupcakes and an "Uberiffic Cat Pack."

The company warned that "Demand for kittens will be very high and availability very limited," and that was certainly true.

UberKittensMany users who attempted to request UberKITTENS delivery received a notification that read, "Sorry, all kittens are currently being snuggled. Please try again soon!"

Uber teamed up with meme site and local animal shelters in New York, San Francisco and Seattle for the cat deliveries.

All proceeds from the snuggle sessions were donated to the shelters, and people who used the service were given an opportunity to adopt the kittens.

This isn't the first time Uber has made headlines for its unusual deliveries. Earlier this year, the car service partnered with condom company L to deliver free condoms, and when Boston school bus drivers went on strike, Uber transported students to public schools.

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