Roboform Christmas tree
From Tardis Wiki, the free Doctor Who reference
The Roboform Christmas Trees were used by the Roboforms to wreak havoc among Earth during the two christmas invasions. These remote-controlled trees can spin at extremely high speeds and rip apart everything in their path. Another feature the trees have is to send bombs disguised as baubles flying everywhere. (DW: The Christmas Invasion, The Runaway Bride) These baubles were used by the Doctor to decimate the Empress of the Racnoss and her children. Like many other robots, they can be stopped using a sonic screwdriver.
