Grew some grass for my cat and she loves it!
This is our queen, Princess. She is strictly indoor because she hates everything else that moves, other than people, but the one time she slipped outside we caught her almost immediately because she just dove into the grass and started rolling. So I grew some grass for her in an old litter box. Wheatgrass specifically, I read it's good for them and aids digestion and some gastrointestinal issues, and the grass is very soft. To sum it up, SHE ABSOLUTELY LOVES IT. I can hardly get her put of her grass box, she has also started eating the grass and has less gas and her poo doesn't stink as bad...
She loves it so much I had to show everyone I could and if you have an indoor cat they might love it too!
It was really simple to make and you can use what ever grass you'd like. I just chose wheatgrass for some of the above mentioned reasons. I just took an old litter pan, put holes in the bottom to drain, dumped in some potting soil then dumped in my pack of grass seeds and let it grow! It took about 3 weeks to get this full, plus I dropped it and spilled it but its still fine.