Through a SideCar app, travelers can get a regular person looking to make a little extra money to drive them around for a “donation.’’

JAKUB MOSUR For The Globe

Pinterest, with 75 employees, is growing so fast it can barely keep up.

JAKUB MOSUR For The Globe

Ben Mathes, Kyan Pardiwalla, Kevin Montag, and Joshua Slayton at work in the AngelList office last week.

SCOTT KIRSNER FOR THE BOSTON GLOBE

Coupa Café is a popular hangout for entrepreneurs in Palo Alto.

SCOTT KIRSNER FOR THE BOSTON GLOBE

A pedestrian stopped to show off his electric motor-powered Boosted Board.

JAKUB MOSUR For The Globe

Audrey Kim, assistant to Paul Graham, talked with Jarred Tame and Teng Siong Ong, two young entrepreneurs, at the Y Combinator office.

SCOTT KIRSNER FOR THE BOSTON GLOBE

Scott Kirsner got to test drive a Google Glass, a digital display mounted on an eyeglass frame.