Apple (AAPL) is finally getting a toehold in the corporate world, thanks to the iPad.

Companies that have historically resisted Apple products are snapping up iPads, The Wall Street Journal reports. Half of the companies in the Fortune 100 are buying or testing them, and at least 500 iPad applications are specifically for use by businesses.

• Find a better broker and trade online

"Everyone in IT is jumping on this one," an analyst told the Journal. "Rather than wait for people to start complaining, they're saying, 'Why don't we get a few of them in and see what they are good for?'"

That's quite a different story than in the past, when tech departments were loath to service multiple operating systems and hardware configurations. More diversity brought more security risk and costs.

Why is the iPad so different? The Journal says the device is "more of a known quantity" from a technical standpoint. The iPad works well with Exchange, the e-mail server software from Microsoft (MSFT). Employees can also connect securely to corporate networks. Also, companies can develop their own iPad apps to use internally. (Microsoft publishes MSN Money.)

The Journal also says iPads are cheaper than many laptop computers and are useful when employees give demonstrations.

Some car dealerships use iPads so that salesmen can begin the credit application right next to the vehicle, the Journal reports. Bausch & Lomb sends iPads out with sales employees in the field.

Still, iPads in the workplace are an anomaly at this point. But you can bet that this nascent business interest is a big reason why all kinds of computer makers are rushing their own tablets out the door.