WASHINGTON (REUTERS) - Internet sensation Grumpy Cat's 15 minutes of fame look set to continue.

The cat, famous for its scowling face, had a busy few days as it not only unveiled a waxwork at Madame Tussauds in Washington, DC, on Wednesday (Sept 28), but also joined the cast of musical Cats for their finale on Broadway.

At Madame Tussauds, where famous people - and apparently, animals - are immortalised with a waxwork, Grumpy Cat sat alongside its doppelganger and was photographed with various former US presidents and in numerous presidential locations.

When asked how she was feeling, her owner Tabatha Bundesen said: "She was thrilled. As you can see, she's still thrilled." Grumpy Cat stayed in her arms with its usual scowl.

On Friday (Sept 30), Grumpy Cat was the guest of honour at the curtain call for the Andrew Lloyd-Webber musical Cats.

Ms Bundesen, who according to reports could have already made up to US$100 million (S$136 million) from her pet, has said that Grumpy Cat's facial expression is caused by feline dwarfism.