I see Maplins in the UK have a multivoltage AC (not DC!) output wart. But, they don't manage to say what the voltages are, on their website.
I'd like to hear of any similar items, in ANY country. They sure would be useful at times..
Radio Shack in the U.S. has two:
//www.radioshack.com/product.asp?catalog_name=CTLG&category_name=CTLG_004_001_001_000&product_id=273-1631
http://www.radioshack.com/product.asp?catalog%5Fname=CTLG&category%5Fname=CTLG%5F009%5F001%5F001%5F002&product%5Fid=273%2D1690&site=search