Toys I have tried that work with Dixie:

• "Buster Food Cube."  I found this at Petsmart, after a suggestion by my vet.  The cube is made of plastic with several compartments inside and one hole outside.  You put dried food (or dried cereal-a treat) in the hole, shake the cube around for the food to get in the compartments, put it on the floor, and your pig will be rolling that bad boy around in no time trying to make the food roll out.  This is known as a type of manna ball.  You can make one of your own by taking an empty, clean container of your choice, putting holes in it big enough for food to fall out, and putting some treats inside.  You probably want to make the holes small enough so the food won't come out easily, but will eventually fall out.
• Laundry.  As weird as this sounds, take all your laundry and throw it on the floor.  My pig likes to root it around and cover herself with the laundry.  Be careful, though, because my pig has tried to chew buttons off of shirts.
• Blankets and sheets.  I have a futon that Dixie can climb onto.  She likes to root blankets around, snuggle under the covers, and fall asleep.  You could try this tactic with a bunch of old towels and sheets (go find some at a yard sale if you don't have any.)
• Newspaper.  Yes, newspaper.  If you read a newspaper on the floor, watch your pig.  He will come over, look at the paper, and all of a sudden bite on a corner and run off with it.  Other people have told me that their pigs have this same fascination with newspaper; for some reason, pigs think that paper is great fun to snatch away, shred, and chew up.  I think it has to do with the noise the paper makes in the process.
• Throw pillows.  I had a couple of old throw pillows, so I put them on the floor, thinking that Dixie would like to lay on them.  She does, but she'll also stick her nose under them and try to toss them in the air.
• Plastic grocery bags.  I am now convinced that pigs love things that make noise.  These are better than newspaper because the pig is not as likely to eat plastic, since plastic is harder to tear than paper.  These bags are also not big enough for the pig to get caught in and suffocate.  Dixie loves nosing and pawing these plastic bags.  She will also grab them in her mouth and shake them.
• Goodie ships.  I found these at PetsMart.  They are made of rubber and have star-shaped holes in them.  You are supposed to put food in the holes.  These toys are shaped like flying saucers and come in different sizes.

• Balls.  I read on someone's pig page to take a bunch of balls (any type, as long as Dixie could not swallow them) and put them in a closed-in space.  Dixie would then like to root the balls around.  Well, after having 36 golf balls, 40 tennis balls, and  being $60 poorer, the most fun Dixie has gotten out of the balls has been trying to rip the plastic off of the tennis ball canister.
• Fleece toys.  I bought Dixie a squeaky fleece toy that has 5 rope legs extending from it.   I usually find it in her litter box when I come home.