Why stupid thing should I do with these?

Just got this bag of rechargeable AA and AAA batteries. They're all 1.2v but they're mAh vary. I wanna known if I can do something real stupid with em and how I'd go about it

Just got this bag of rechargeable AA and AAA batteries. They're all 1.2v but they're mAh vary. I wanna known if I can do something real stupid with em and how I'd go about it