caramac:
Ah yes, those hidden pics... I guess they just put them in there to annoy the hell out of free gallery collectors woh use spiders...
No, actually.
The free pictures are prepared in advance then later added to a template according to the recipe of the tgp-site where they will be posted. Some sites require 15 photos, some 16, 18 or 20 photos. This way, the tgp-galleries remain flexible with no additional work required at a later date. This is also the reason that you will see the same free pics appearing again and again at different sites.
greets - mike =))