[semi-extrinsic]

For remote surveillance, you can use a laser microphone up to 4-500 meters away from the target house. No hardware or software in the house required.

[jcims]

With a $20 dongle you can perform TEMPEST attacks on the display itself.

https://www.rtl-sdr.com/tempestsdr-a-sdr-tool-for-eavesdropp...