How does it go?  "A rolling stone gathers no moss"?

While that may be true of rolling stones, it is certainly not true of this former Heliocol customer's rooftop.  Thanks to Tom Lane of ECS Solar for sending this one in...

[caption id="attachment_648" align="aligncenter" width="640" caption="Click the image to view larger"]<a href="http://www.aquathermindustries.com/portal/news/wp-content/uploads/2012/04/Heliocol-Moss.jpg"><img class="size-large wp-image-648" title="Heliocol Moss" src="http://www.aquathermindustries.com/portal/news/wp-content/uploads/2012/04/Heliocol-Moss-1024x768.jpg" alt="" width="640" height="480" /></a>[/caption]
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