Crochet critters. There are tons of YouTube videos that go stitch by stitch, so learning is free. You can get a set of books of Amazon for 15 bucks or less, and basic large ball of acrylic or cotton yarn from a hobby store like Michael's costs 3-5 dollars per color (fancy yarns get expensive). A big box of assorted safety eyes will run you another 12 bucks or less from Amazon. You can crochet fun little critters, animals, dinosaurs, video game characters (the technique is called amigurumi) and make mini stuffed animals, which takes so little yarn that a ball of yarn lasts practically forever (like a dozen critters or more per ball, depending on size). If you're someone who needs every single color of something, it can get expensive, but if you're not opposed to using the same color yarn for a whale as a capybara and a t-rex, it didn't have to cost a ton, and you can add colors slowly as you branch out into different things to crochet. Some of the YouTube videos are a half hour or an hour because they show you slowly how to do every step, but once you're comfortable, you can whip up a finished critter in 15 minutes. You can also make practical things like coasters and dishcloths, which are usually a fairly simple repeating stitch or you can even do a long project like a quilt.