Sonic cane

The sonic cane was a sonic device used by the Eleventh Doctor while his regular sonic screwdriver was indisposed. He used it to scan the Teselecta and, having given his screwdriver to them, to contact Amy Pond and Rory Williams through the two sonic devices while they were miniaturised inside.

Similar to the Eleventh Doctor's sonic screwdriver, the sonic cane emitted a green light and featured four "claws" which popped outwards to reveal the green light. It also recognised a signal from the sonic screwdriver. (TV: Let's Kill Hitler)

The Doctor would once again use the sonic cane at the home of Lord Cranarch, Repton Abbey. While at dinner, he discovered that the servants and dinner guests had been taken over by reptilian aliens led by Lord Ryzt. The bodies of the humans they replaced were kept alive in a stasis generator to store the memories, which were fed back to the aliens. Upon discovering this, the Doctor used his sonic cane to overload the alien minds, flooding them with too many memories at once which released the control over the houseguests. (COMIC: The Demons of Repton Abbey)

Behind the scenes
The sonic cane was made into a DWMI Card in September 2011.