Colour changing unicorn mood light from the hut on eBay. The same thing on Zavvi, the hut and I want one of those is £9.99 but charging £2.99 postage on top so grab this as a stocking filler for a bargain price.
Needs 3 x AAA batteries which obviously aren't included but it has an led bulb so it should be super power efficient.
Now £9.99 but spend £30 and save £5 on lots of other unicorn themed stuff
9cm high x 10cm wide x 13cm deep