Just in case anyone's interested - I've just found
ImageSynth which is a new photoshop plug in from Luxology (who do the modelling program Modo.)
To quote from the website:
Quote: "imageSynth is advanced technology that works within Adobe Photoshop for creating seamless textures and for creating high resolution images from low resolution sources using advanced image synthesis algorithms. Hence the name!"
Looks interesting!
BLACKMESA:SOURCE - mod for HL2 - Texture Artist
BIRTHSTAR:FRONTLINE - Texture & Environment Artist