"Cats Don't Rent, They Own!"

Socks actually belonged to my downstairs neighbor but she had too many cats and had to get rid of some.  Socks spent a lot of time with me up on my balcony and when I heard he was on the list to go... naturally I took him, which seems to suit him just fine.  He is a black and white "tuxedo cat" (neutered male) and is 5 years old.  Socks has an unusual habit (at least it is to me)... he likes to bring me presents.  The unusual part is that the gifts are always children's toys and I don't know where he is getting them from so I can return them.  I feel sorry for the kids who these things belonged to.  Here is just a sample of what he has carried home:

3 Barbie dolls, 7 various other dolls, 4 various beanie babies, 1 child's slipper w/ Donald Duck on it and 1 child's slipper w/ Scooby-do, 1 plastic American Flag, 1 child's snorkel mask in the shape of an elephant's face, and 1 child's Wilson's blue leather baseball glove (like new).  And many other various small trinkets he can carry.  He carries them up my stairs and drops them at my door and then gives a funny little cry.  When I open the door he leaves the toy outside and comes in.  Once when it rained he brought in one of the Barbie dolls but I told him I wouldn't feed her too!  

Has anyone else ever heard of a cat doing this?  And do I need to be concerned? 
 

Socks' favorite things are: (besides what's mentioned above)

 Lots of attention from me

 Food

 Catnip toys 

Sleeping

 Catching bees and playing with them until they die 
(don't know how he does this without getting stung but I find dead bees on my balcony all the time, and I've seen him carrying one in his mouth)
  

Here are some additional pictures of Socks
(click on picture for a larger image)