Cornelius

This is about the closest thing, so far. Too bad it requires Adobe Illustrator or CorelDraw; those suckers are expensive. I tried the link but it doesn't work. Either way so far I haven't seen any interactive tours of Rome(or at least not any good ones), which suprises me, although doubt it will be long before someone does it.

The Lorica Segmentata for a while was believed to be made of leather, because the statues/carvings (ie Trajan's Column) typically depicted a muscled cuirass leather in appearance. Recently however this idea has been disregarded, unfortunately I do not know the details as to why, but it is more widely accepted now that the muscled cuirass was in fact metal. The Greeks and Corinthians had their muscled cuirass's made of metal, and chances were the romans did not use much leather in armor. There is a possibility that some Roman troops wore leather armor at a time, but I believe the farthest the use of leather by the legionaires went was it's use as subarmalis. The enemies definately wore leather armor, because Roman literature mentions it. I suppose in an RPG environment you could introduce something like that, although I've never been in an RPG where playing strictly to reality (even on questionable facts) really mattered.