Our product is a presence-aware power outlet (https://www.kickstarter.com/projects/dobots/crownstone). It went like crazy in the first few days! However, we didn't get traction in the US for now.
It might be just the fact that we got unlucky about our media coverage on the big American tech sites.
However, perhaps you have better ideas about the mechanisms that make an open-source product like this go viral.
Any insights will be really appreciated!