The most effective way to handle this would simply be to get the information about this nasty, greedy theft back to the gift-giver AND to his employer. The 'transaction' is almost sure to get back to HER boss as well--she either stole from the named employee, or stole from him. Reputable, honest businesses don't take kindly to such things; This could be your magic moment to get rid of this petty b*tch.