Why even require a wallet for your site? Use something like Inputs.io's on page payment buttons - when they want to buy something for example, they can make the payment right from their wallet without leaving the page.
More thinking along the lines of gambling on weather at airports around the world Highs/Lows/Precipitation. Maybe way over my head, if you would be interest in building something like this I would be happy to pay.
Edit: unless there is already something like this.