While advances in print technology threaten to render authenticity in the visual arts obsolete, the Swiss National Bank remains an obdurate protector of the genuine. Last year, the bank issued its latest series of "counterfeit proof" bank-notes. Realised by Zurich designer Jörg Zintzmeyer, the prismatic currency maps the new world of microtext, watermarks and optically variable ink. The beauty and complexity of these notes suggest that tangible currency has secured its future - for a while, at least.