I often hear that kids love the packages of the toys more than the toys. In Jens case, he loves rubbish more than his toys or anything that crackles. I haven't let him play with the boxes of his toys as I am saving them for when we need to put away the toys.
Look at the toys that he loves playing with.
the mail envelope the biscuit tray the salad container
If he'll stay like this, we could save heaps of money for not buying toys at all. Just throw pans, plates, papers or any plastic container and he'll have more fun with them. :)