split open a small cushion which a watch was on and found a huge amount of this fluffy stuff that lighted with a spark like a treat, it feels kind of synthetic and silky..............what is it and is it dangerous to burn??
Sounds like polyester batting -- don't burn it, the gases are noxious.
There are plenty of natural sources of tinder in your house and garden and nearby areas.
As was mentioned earlier in the thread, dryer lint is a great source of tinder if you wash cotton or linen items. (For that matter, shred an old 100% cotton t-shirt, hit the fibers like crazy with a hammer on a hard surface to crush the threads and you've got plenty of tinder... or if you have a fireplace, save some of the t-shirt and make some charcloth as well...)
Also, if you have wood projects about, save the shavings to use raw, or mix them with a little bit of paraffin or beeswax to have a reliable wet burning tinder. I save any hardwood shavings from my bow projects specifically for using in this manner (FYI, you don't need much wax/paraffin, just a little).
You're surrounded by tinder, really.