Poundland is selling a cool bath bomb that leaves a pretty rainbow trail in the water – they’re bound to be a hit. The fizzy bath products are shaped like sweet little clouds and cost just £1.When you dip the white cloud into the water it will fizz up into a rainbow of colours.The label said: “Gently place me in the bath and watch the rainbow appear.”The gorgeous bath bombs would be perfect as stocking fillers or secret Santa gifts at Christmas.They sold out when they went on sale in Poundland in February this year – but have now returned to stores. What's your favourite bath product to use and why?