From wikipedia

"Cha-Ching" is the first single from Hedley's third studio album. The song entered the Canadian Hot 100 at #34 on the 36th week of 2009 and ended up reaching the top ten peaking at #6. It is about reality television shows being fabricated, and references several TV shows and stars.

Imitative of the sound of a cash register when an amount is rung up. Popularized in 1992 by the movie Wayne's World [1] and by a 1992 advertisement featuring Seth Green

cha-ching

1. (US, Australian) Score!; Wow!; said to celebrate something that has made or will make lots of money.

cha-ching

1. To make a cash register or slot machine noise; to make the noise of coins falling.