KONGS: I thought kongs were indestructable too, until one day I heard this horrible sucking noise under the table.
Ginger had removed the top of the kong and it was lodged in her mouth. Fortunately, it was too big to go down the throat and I was able to remove it. Now I inspect her kongs frequently. They are pretty tough, but don't be fooled. Nothing is completely indestructable.
Other indestructable (or nearly) toys that I've found: 1. PETSTAGES orka jack (with or without rope). Ginger loves this toy. So do all the dogs at small dog club. No one's destroyed either of ours yet. It's available at Petsmart and Target
2. at TARGET I bought a tennis ball bone (it's pink, but they also had blue). So far seems pretty indestructable.
3. from J&B wholesale I buy real bones. Most dogs aren't interested, but Ginger loves them, and can chew on one forever!