San Jose, Calif. - The jackpot-sized venture capital investments last year reveal a few things about Silicon Valley's tech scene: Uber's IPO seems imminent, investors are convinced Airbnb can't be beaten by a competitor, and unlike years' past, it's now pretty common for a company to nab two huge investments within just a few months.

There's a whole lot of money going around, and if your name is Lyft or Instacart, investors are piling on the dough without hesitation.

Last year, there were 22 venture capital investments in Silicon Valley of $120 million or more - nearly half of all the so-called mega deals, or tech investments that top $100 million, in the entire country for 2014, according to the MoneyTree Report, produced by PricewaterhouseCoopers and the National Venture Capital Association. And only in Silicon Valley did funding rounds top $1 billion last year, according to the report, which uses Thomson Reuters data.

As investment rounds balloon in Silicon Valley, VCs are able to handpick the winners, filling the war chests of their favorite startups with so much cash that the competition stands little chance of catching up. The top 10 deals last year accounted for about one-fifth of the total investments in the valley last year.

"People really pile into the winner, they really lean in, and they invest very heavily," said Anand Sanwal, co-founder and chief executive of CB Insights.

Uber, for instance, raised an unprecedented $2.4 billion in two separate rounds; Lyft raised $250 million, a respectable sum, but just about one-tenth of Uber's arsenal.

"It's a vote of confidence in both the technology and the team at Uber," said John S. Taylor, head of research for the National Venture Capital Association.

Six of the top 10 VC investments in the valley went to ride-hailing services Uber and Lyft, online house- and apartment-renting service Airbnb, and grocery-delivery upstart Instacart - with Uber and Airbnb each claiming two separate deals. This collection of companies falls under a single category known as marketplaces - apps or websites that connect a person selling an item or service with a consumer who wants to use that item or service.

The surge of investments into this sector last year - $3.5 billion for those four companies - underscores just how excited venture capitalists are about these types of apps. They are fairly inexpensive companies to run - Airbnb, for instance, doesn't have to build and maintain hotels, or pay hotel staff, said Neil Sequeira, managing director of VC firm General Catalyst Partners in Palo Alto. And they are easy to grow quickly, because they don't need a physical office in every country - just consumers with a smartphone.

"The reason they make better investment is they are very high-margin at scale," he said. "You're basically just closing a transaction. You don't get that dirty."

Other companies that got investors' attention: Pinterest, an app for sharing and curating ideas and projects, raised $200 million; and Palo Alto-based Houzz, a website to help homeowners remodel and design their house, added $165 million to its coffers last year.

"Houzz is going after a market that is almost half a trillion dollars every year just in the U.S., and probably twice that internationally," said Hany Nada, a managing partner with GGV Capital, a Houzz investor.