While the heyday of the Slinky may have been a few decades ago, I still think it's one of the coolest toys to ever go to market. Not to mention it probably has the best commercial ever created.
If you still have an old Slinky lying around, you can make this pretty cool bird feeder. All you need is an old wire hanger, string or super glue, and some peanuts. There is an actual product out there that you can buy (pictured below, left), but the DIY method (pictured below, right) is cheaper and just as effective, though a little more rough (but I highly doubt the birds will mind).
To start, take the wire hanger and begin stretching it into a circular shape. If you have a large round pot, you can use it to help create the shape. You're going to want it to be as smooth as possible, so make sure to get all those hard bends out.
Once you've made the hanger into a circle, you can untwist the top. If it's too difficult to do by hand, grab some pliers to get the twists out. With the top open, slide the slinky on.
Now, stretch the slinky out and super glue or hot glue both ends to the top of the hanger.
Now we're pretty much done. All that's left to do is add the peanuts. Just dump a bunch into the the openings at the top.
Hang your finished slinky bird feeder on a low hanging tree branch or a porch hook if you have one. Check out the tutorial over on Kiss My Smash for more details and photos of the process.