This week Mattel launched PlayBack, their initiative to recover and recycle used toys (of their own manufacture). Whether unwanted, outgrown or simply broken, the company will e-mail you a free shipping label for them. You ship the toys back to them as-is--no cleaning necessary--and they recycle the recyclable bits to be used in new toy manufacture.
As for the other parts "that cannot be repurposed as recycled content into new toys," the company writes, "we will either downcycle those materials into other plastic products or convert them from waste to energy."
Mattel does stress that "we encourage you to donate toys in good condition to a local charity so that children can enjoy them for as long as possible." Failing that, they're ready to take them.
Initially, the program can only handle Barbie, Matchbox and MEGA toys, and are only serving the U.S. and Canada. Plans are for the program to expand to include more toy brands under their umbrella, as well as to launch the initiative in the UK, France and Germany.
If you've got a box of these you're ready to ditch, you can get your shipping label here.