There's no better way to discourage a dad from taking the baby for a walk than to hand him a flowered diaper bag and a stroller that's too short, forcing him to bend forward when he walks.

A dad needs to be able to be cool. He doesn't want to hunch, he wants to throw out his chest, in pride, when he's out with the baby. Also, a dad needs to be able to hold his own in discussions with other guys, discussions about wheels and ease-of-handling and other vehicular topics.

This according to Greg Allen, who used to live in Utah but who now commutes between New York City, where the Allens keep an apartment, and Washington, D.C., where his wife, Jean, works as an astrophysicist. Allen makes films. But three or four days a week he's a stay-at-home dad, caring for their daughter, 3-month-old Ada.

Before Ada was born, Allen and his wife went shopping for infant gear. "In the process of trying to find stuff I could stand," he says, he started a Web site called daddytypes.com. On his site he writes amusing critiques of baby toys and furniture. (Unable to find a changing table he liked, he spent $50 on a bright red metal tool cart and outfitted it with a pad.)

His site links to Web sites of other dads. And other fathers e-mail Allen with their own discoveries. (Lately, they've been alerting each other to the location of changing stations in local men's rooms.)

Perusing Allen's Web site, as well as some of the others he links to, you might conclude that today's new dads fall into one of two categories: Gear-heads or geeks.

To the uninitiated, gear-heads and geeks may seem equally enamored of baby stuff. But there is a difference between the two types of dads, explains Salt Lake father Jon Armstrong. Gear-heads come to the fatherhood role from a background in sports or camping. Geeks come to fatherhood from a background in computers.

Armstrong used to live in San Francisco, where he was an art director for an online magazine. He's a geek, he says.

"Geeks always look at how things are designed," he says. "If there is a clever aspect, that appeals to geeks." This year, with the birth of little Leta, Armstrong is in design heaven.

Even before Leta was born, Armstrong noticed the Baby Bjorn carrier. He knew he and his wife, Heather, had to have one. They were so much easier to use than the previous generation of infant sacks and slings, the kind of carriers he'd watched his older siblings use with their kids.