Here's the reply I received today - so maybe it is worth a bit of sabre-rattling.
Çäðàâñòâóéòå, Stuart.

BE DELETED!

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Ñ óâàæåíèåì, Þ
  www.ArtFile.ru

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Âû ïèñàëè 13 ìàðòà 2007 ã., 2:30:13:

S> http://www.artfile.ru/oboi/b/i.php?i=a|242110
S>
S> I am the artist who created this image and gave NO permission
S> for it to be hosted at this your website.
S> This image has been STOLEN from www.renderosity.com and I
S> demand you remove it from your website immediately.
S> You should also ban 'chris' who posted it.
S>
S> Thank you