(Image: supplied photo)

Here's a nifty gadget if you're in the anti-advertising camp -- a gateway that blocks ads for anyone who connects.

California startup XOware lets users who work on unsecured networks at a coffee shop or airport connect securely through a $40 XOkey USB device. This hardware stick works with an XOnet gateway, a $70 compact router-sized box, which sits in a secure location -- like your home or office network.

Thanks to a software update earlier this year, the XOnet box now provides ad-blocking -- allowing anyone who connects to be protected from potentially unsafe ads, without requiring browser plugins or extensions.

"We implement ad blocking by maintaining a blacklist of servers, and looking up all addresses on the list before performing a DNS lookup. If a URL that is requested by a client device is on the blacklist, we ignore it, so the data is never sent to the connected device," said chief executive Ken Goldsholl in an email.

Users are able to add sites manually to the white list, he added.

Ads keep websites free for everyone to access because they drive revenue to content creators. Ad-blockers cut off that supply by ridding your screens of flashy, garish, and memory-consuming ads. But also they serve as a safety net for malicious ads that slip through the net.

The company said the firmware release also adds a firewall and technology that reduces data consumption on mobile devices.

Both the XOkey and the XOnet use run-of-the-mill open-source cryptography and protocols, like AES-256 and IPSec. It's worth pointing out that no device is ever perfectly secure, but it's certainly an interesting and novel approach to securing data over an unsecured network.