Yes - when you pvp and win against another player, their ship is destroyed, but not all the equipment on it or items in the cargohold are. Its often profitable to loot the wrecks left after pvp - the modules can help repay people on your side that had losses or just general make you rich (some gear is worth hundreds of millions of isk and are often fit by idiots - although in the case of titans really good gear is necessary given their 40billion isk average cost.) Also you cna then actually salvage the wreck for components to make rigs too.
Ex-BoB/Kenzoku Killboard has values for that loss:
http://www.killboard.net/details/304886/Although the faction & officer gear: Rayseres, Corpum, Centus C/A-Type etc is all waaaaaaaay undervalued due to the fact that gear is not sold on the market it is sold via player contracts (a system that cannot be accuratley datamined)
