These ads make you smile, feel almost warm inside - a funny bear costume, fairy cakes with sprinkles on - until you remember that they are fundraising for the prevention of cancer. Copywriters don't make use of the word 'kill' lightly but these ads say: we can do that, lightheartedly, with comedy - whatever it takes - because costumes or coffee mornings, it all adds up. And that means the difference between life or death for someone. Cancer Research use these adverts - together with a video campaign.