I was recently asked this question by a friend from the South. Since the town I live in is basically the 'Crow Capitol', they expected me to know the answer. I told them 'roadkill' and 'garbage - particularly if there are old chicken wings in it!'.
DH & I have learned that we can NOT put our garbage out the evening before pick-up, as we will just be sweeping, retrieving and re-bagging it ALL again in the morning. The photo above is the scene left on the sidewalk after pick-up this morning. Our bag was only our there for 1 hour!!
Further down the sidewalk, I noticed some 'left-overs' from a neighbor who had apparently put their trash out last night...
...so I guess the answer to the question will now have to include 'cigarettes'?!!