Remember, starting fluid IS NOT PURE, it contains heptane and/other petroleum distillates and these will compete for oxygen being absorbed into your blood stream.
This is dangerous and WILL kill brain cells.
... And inhaling ether,
which also competes for oxygen, isn't toxic? The real reason you want to avoid petroleum distillates, is because some compounds like hexane get metabolised to neurotoxins. And they do e.g. defat nerves and the like, they're solvents. In the grand scheme of things, heptane is pretty safe though - it does not metabolise to a neurotoxin like hexane does. The important thing is that you alternate between breathing vapours and then breathing air - that is, dont lay down with a rag on your face, or you'll probably not wake up. (Heptane is actually the major component of Jeffery pine turpentine.)
I digress.
Huffing ether is stinky. very stinky. Ether boils at around 35C, just under body temperature, which means the main way it leaves your body is not through metabolism or urinating it out, but rather on your breath. So if you ingest ether, be prepared to smell like a paint marker for a day or so. It's also flammable as Satan's aftershave. The vapour is heavier than air and will "creep" along the floor, and if it finds an ignition source it can ignite. Also, it has a very high latent heat of evaporation - meaning when it evaporates, it makes things very cold. If you're huffing it off a rag, the rag can get frosty, and if you make direct contact on your skin it can lead to frostbite as well as solvent burns. (Ether dissolves the fats in your skin).
The experience is very similar to being incredibly drunk. With a dose of maybe a teaspoon or so, you can achieve a floaty, relaxed state. Inhaling more (up to maybe 50ml) will eventually lead to a semi-hallucinogenic stupor, loss of motor control, dissociation, and out-of-body experiences. The peak effects last maybe 5 or 10 minutes - ether readily evaporates - but can be extended somewhat by redosing.
For the amount of stinky, flammable vapour huffing ether produces, and the short duration of the "high", it's not really good for much more than a curio. Certainly not a party drug. Go read Erowid for more info.