05 Jun 2005 at 18:09 - 2
When you salvage it you have a chance of getting common crafting materials (such as wood or iron, I don't know which one hammers give) or upgrade materials. Maybe rare crafting materials sometimes. So you may get iron/steel, or an upgrade piece with one of the special abilities of that hammer.
That hammer would have been worth a lot if it weren't customized. But since it is customized, no one else can use it. So pretty much it is worthless, that's why even if you salvage it and get an upgrade or a bit of crafting material, it will still be worth more than the whole hammer as other people can not wield it and see it as worth zero gold.