Fidgets are awesome. One thing I like about them is that many of them are CHEAP. Sure, some of the high-end stuff like Thinking Putty may be $10/can but you can get a hackeysack or stress ball at a party store for $1.

If you're crafty, you can even make your own.

https://www.pinterest.com/explore/stress-ball/

http://www.yvonnereynolds.com/blog/2013/01/18/fabric-marble-maze-tutorial

https://www.pinterest.com/explore/fidget-toys/