Free data available?

Hi, I'm like so many others trying to invent the method that gives a big enough plus, using fixed rules. I have such a method that on one FX gives a considerable amount of points, based on the historic data. I want to test that method on a lot of other FXs and Indices and Commodities to see which react best to this method. But currently getting the data to test on in excel is very cumbersome and I get data where numbers are sometimes formatted as text etc. Takes forever.

So, where can I (free?) get historic data? I need approx the last 15 days with 1 minute intervals.

Thanks

Free data available?