Best cat toys you've invested in?

Please post pics

Cat tree

(Not actually my cat tree but u get the idea)

Edit: i didnt generate this photo, its a link to an image that popped up. For the record, that would actually be a sick cat tree and I would buy it if it was available and I had the space for it which I do not)

Take the tinfoil wrap off of a Hershey’s kiss up in a small ball, then take several more of those tinfoil wraps and keep wrapping until you get a ball approximately a quarter to a half inch across. Then toss it on the floor near the cat.