Silicon Valley is in the midst of a great corporate baby boom. Venture capitalists have pumped $2.5 billion into 400 young Internet companies since the beginning of 2006, compared with $1.3 billion into 236 companies during the previous two years, according to research firm Dow Jones VentureOne.

These entrepreneurial brain children have short life expectancies, destined to fight for revenue with the likes of Google, Yahoo and EBay. But still they are being born — and they need names. Naming a company is far more difficult than naming a child. The name needs to sound snappy, separate its young company from the pack and provide a unique Web address.

You won’t find a name among the horde that conjures up traditional companies such as Dress Barn, Best Buy and Burger King. Most Internet company names make little sense, and they roll around the mouth like a marble.

“Old-school ideas about sounding trustworthy or sounding big are not as important as they used to be,” said Burt Alper, co-founder of Catchword Branding in Oakland, which has helped companies pick such names as Vudu (makes a device for watching videos) and Promptu (creates voice-recognition products). “Now it’s about sounding different and standing out from the crowd.”

Like naming a new baby, the process involves late-night brainstorming, some expert help and a dose of frank feedback from friends. And like the grandparents-to-be, a company’s financial backers can kill a loved name with a raised eyebrow. Picking the wrong name can kill a multimillion-dollar investment.

Entrepreneurs today pick names they think will help their companies stand out, as do parents of little Zander and Arlo, Eliza and Matilda. “Naming a company is like naming a celebrity,” said serial entrepreneur Jared Kopf, who has helped christen companies including Adroll.com, his online advertising firm, and Slide, a Web photo service. “Made-up words don’t come with psychological baggage.”

Call it the Google effect. Thanks to the successful Internet search company with the goofy name, entrepreneurs feel no shame telling people they work for ItzBig (career networking) or asking venture capitalists to invest millions of dollars in Picaboo (a website for ordering custom photo books). Who needs the gravitas of an International Business Machines or a General Electric?