After enjoying another weekend, it's time to settle back into the office again at the start of a new week. If the coffee isn't strong enough to keep you going, maybe this great mashup of Katy Perry's 'Roar' and Sara Bareilles' 'Brave' will cheer you up.

When 'Roar' first released, there was speculation surrounding whether or not Katy Perry had ripped-off Sara Bareilles' song. Since then both singers have shown their support for each other via twitter and other media.

In fact, Katy has invited Sara to be a part of a special performance at the Hollywood Bowl to help raise awareness and funds for young women with breast cancer. The concert called, "Katy Perry's: We Can Survive" is set to take place on October 23rd, just one day after her album Prism is released, and will include Ellie Goulding, Tegan and Sara, Kacey Musgraves as well as Sara Bareilles.

"These are all very powerful women that I really respect and look up to, and I wanted them to come together to promote this supportive message and have a fantastic night full of great music," Perry said to of her involvement. "There's so many great acts in this lineup. And I get to play a lot of songs off the record that will have come out the night before."