Israeli researchers have designed a device that picks up on laptops' radio emanations to then determine individual users' decryption keys.

All the device requires to function is to be approximately 19 inches away from the target, the white paper stated. Although similar attacks have been launched in the past, this one differentiates itself through the device's small size, its laptop spying and its low build cost.  (The researchers specifically cite fitting it inside pita bread and have abbreviated the device PITA.)

The Portable Instrument for Trace Acquisition can be altered to collect a cache of stolen data on an SD storage card or to transmit it through WiFi to the remote attacker.

Although the researchers primarily focused on extracting keys stored by GnuPG, an encryption software, the device can also collect keys from other crypto systems that use RSA and elGamal.