[MartinCron]

That reminded me of one false positive that may be of interest to the HN community:

I was buying a custom-made suit at Indochino's "traveling tailor" event. It was at a pop-up storefront in Seattle (where I live) but my bank thought their mobile point-of-sale card processing system was in Vancouver, BC and declined the transaction until I explained to them what happened.

And the suit? It's wonderful.