A pop star has rewarded an honest taxi driver who returned the bag she left in the back of his car - with a pair of knickers.Twenty nine-year-old Serbian singer Tina Ivanovic offered money to Toma Majstorovic after he returned her handbag, which had been left in his car after a trip to a beauty salon in Belgrade.But instead of taking the money Majstorovic, who earns £200 a month, said he would prefer a pair of her knickers.Ivanovic was happy to oblige with a pair of silk panties.