Hi funnycat ! - welcome to the forum!
- an empty cardboard box....that is replaced with a different one periodically, with entrance(s), peek holes of varying sizes etc etc - use your imagination. (My neighbour with six cats always has a pile of cardboard outside her house on recycling day!)
- beer bottle caps (on a hard floor - great cat hockey pucks!) (don't leave them unattended until you are certain she won't try to put them in her mouth!!!)
- small balls of shiny aluminum foil...large enough NOT to be eaten, small enough so that they don't intimidate the cat...try various the sizes/colours
One of the key points about these toys is not to leave them 'around' too long, or the cat will lose interest. Use a 'cat toy box' hidden away and bring something "new" out periodically.
String can be fun.......ONLY while YOU are around and holding one end! If a cat eats string (also think: wool, thread, dental floss etc etc) that can cause very serious harm to your cat.......life-threatening harm. If it ever happens that you see a piece of such material coming from a cat's anus, do NOT pull it out! Take the cat to the Vet immediately! If it's in their mouth, as in they're about to swallow it....don't pull it out quickly, hold it, pull slooooowly and gently - you may need help in a case like that.
Hope that helps!
the more i learn about (some) people, the more i luv my cats