The Hut are selling "Wario: Master Of Disguise" for the Nintendo DS for £9.93 (inc Del.)
You can get cashback through the usual sites (e.g. 5% Quidco, making it £9.43)
The next best price seems to be £16.00 from Zavvi.
Make your fortune by mastering your disguises!
Sketch a disguise to change Wario!
Use the power of every disguise to explore, attack, and hunt for treasure!
Draw a tail on Thief Wario to turn him into Dragon Wario!
As Arty Wario, create blocks by drawing them!
As Cosmic Wario, touch a target to shoot it!