Hairdryer

A hairdryer was a device used to dry hair, usually after it was washed.

As the Ninth Doctor searched through a stockpile of weapons in Adam Mitchell's workshop in GeoComTex to destroy the last of the Daleks, he identified one of several supposed weapons as a "hairdryer." (TV: Dalek) It was later salvaged and sold at auction as a "heat ray disintegration device" for 80 million. (COMIC: The Fountains of Forever)

Hairdryers could interfere with the Doctor's sonic screwdriver. (TV: Forest of the Dead)

Other references
Gwen Cooper's Mulifinian disintegrator's bulky shape resembled a hairdryer. (AUDIO: Forgotten Lives)