When it comes to perks, few employers can match those that high-tech companies in Silicon Valley have to offer. Whether it's generous salaries, pet-friendly offices, or on-site services such as gyms and yoga classes, corporate juggernauts such as Google, Twitter and LinkedIn seem to have it all.

Behind all the perks and quirks, however, it's serious business. Google, for example is a global company with operations in more than 40 countries and with annual revenues of nearly $30 billion. So it's no wonder the company wants its staff to play as hard as they work.

At the search-engine giant's YouTube video unit in San Bruno, Calif., employees have access to a rock-climbing wall, foosball tables, an indoor putting green, an outdoor Frisbee golf course and a giant red slide, among other amenities, McClatchy-Tribune News reports.

Those kinds of perks are just some of the reasons that many workers would love to work for YouTube and its parent company, which is headquartered in nearby Mountain View.

"Google has an incredible amount of cachet," Dawn Block, a veteran Silicon Valley technology jobs headhunter tells the wire service. "They offer benefits that blow away the competition."

Google isn't the only game in town, of course. Other firms offer similar recreational activities. Beyond foosball -- which seems to a favorite among Silicon Valley workers -- there's also billiards, ping pong, softball teams, video games -- even wine tastings and wine making.

And that's only the beginning. The perks are as unique and innovative as the companies themselves, as the infographic that follows illustrates.