Welcome to Techapella, where top firms trade hashtags for harmonies

Facebook's Vocal Network, Twitter's Songbirds and Google's Googapella showcase their offscreen abilities in San Francisco concert

What's the first thing that comes into your head when you think of Silicon Valley? It might be computer programming, or social media, or internet bazillionaires. It's probably not an a cappella Destiny's Child mash-up where the opening lyrics of Bootylicious have been altered to include the names of technology companies.

"Apple, can you handle this? Twitter, can you handle this? Facebook, can you handle this? I don't think you can handle this."