Resurrect your old PC as a public kiosk PC.

Leaving your old PC in a public space may seem like a sure-fire way to make it someone else’s old PC. But if you take the time to secure it properly, you can get a lot of mileage out of turning it into a dedicated public-access machine. Setting up an old PC for public use is an easy way to give aging hardware a second life. And putting a PC in the common area of your home, your local school, or your place of business provides convenient Internet access for visitors and gives you a great tool for sharing media, accepting job applications at the office, or helping customers share information with your business.

But before you get carried away with the idea of bringing free computer access to the people, you need to take some security measures to protect both the device and your private network. You need ensure that people who use your kiosk can’t monkey with system settings, add or remove applications, or download malware. You should also help protect your users from themselves, by preventing them from accidentally saving documents, browser passwords, or personal information to your public PC.

Fortunately, with the right software, setting up a secure public PC is a cinch. Depending on what you want to offer in the kiosk, you may even be able to rely on Windows’ built-in features instead of installing extra software. The trick is to figure out who will be using your public PC and what they’ll be using it for.

Install kickass kiosk software

Many third-party programs can turn public PCs into dedicated information kiosks—and you can use the same software that big businesses use to repurpose an old PC with far more security and control than Windows provides. Though each piece of software has its own quirks and peccadilloes, nearly all of them protect a system against permanent tampering and preserve both your privacy and the privacy of whoever uses your PC. Some programs even feature automatic restore functionality that wipes away any changes and user cache when at log-off or rebooting.

If you have a little money to spend and if you’re operating on a stricter budget, try the excellent Netkiosk, a free utility that you can use to lock down a PC for public use in a small business, a big house, or a local school.

Don’t forget to practice good security

No matter how you choose to set up your PC, pay attention to the security of the network it’s running on. Whether you’re setting up a general-use PC for a hotel lobby, a local elementary school, or even your spare bedroom, chances are you don’t want the public poking around in your local network. If your wireless router has a guest Wi-Fi access feature, enable it and connect the kiosk PC to the guest network to keep it isolated from your main private network. If you’re repurposing the PC for business use in an office that has multiple business-class routers, create VLANs and/or multiple SSIDs to segregate the public computers from the private workstations. Regardless of which option you choose, take care to classify the network as Public in Windows (which you’re prompted to do the first time you connect), to disable sharing and network discovery.

Keep the physical security of your kiosk and network in mind, too. Mount the PC or tablet in a secure position to prevent theft. If you’re using an old laptop, you can repurpose common laptop antitheft devices to protect the PC while it’s out in public. Use heavy-duty tape or plastic to block access to unused ports, and use cords to prevent visitors from tampering with them. But don’t get too carried away with locking down your PC: The point is to repurpose hardware that you might otherwise trash to serve as a public PC that anyone can use—and whether your DIY project ends up in a business or in a local school, it won’t serve its purpose if people can’t use it to be productive on the Internet.