I have found plastic medical syringes and needles a useful tool for the workshop. One use is to deliver a small drop of oil or contact cleaner to a hard-to-reach place in a mechanical assembly, and you can precisely control the quantity of the drop. I sometimes use them to inject fresh liquid epoxy to a strategic location, but naturally, this application requires a large size needle and makes the syringe a one-use item.
Years ago, those things were easy to obtain if you knew someone who worked in a hospital, doctors office or medical clinic. But these days, with all the paranoia about used needles, needle sticks, HIV, hepatitis, IV drug use, etc, even unused needles and syringes at most medical facilities are treated practically the same as controlled substances, and employees can be fired simply for taking one needle or syringe off premises. They can readily be purchased on line, but if you have immediate use for a tool, it's a hassle to have to wait 10 days for an order to arrive, and I have heard stories of shipments being hassled by postal inspectors.
Nevertheless, I have found a cheap, readily available source of these instruments that are perfectly satisfactory for workshop and craft use; their low price is probably because they are not sterilised to medical standards, if they are even sterilised at all. They are made in China, so would you trust your life to Chinese sterility standards, seeing that toxic chemicals have shown up in Chinese made children's' toys? Other than questionable sterility, these are exactly the same instruments as the ones used for medical purposes.
Go to your local farmers supply outlet, and look for veterinary syringes and needles. Plastic syringes come in packages of 2 for a couple of bucks, and needles come in packages of 5 for about $1.50 total. They come in various gauges (sizes). I find the most useful to be the largest, 16 ga, and the smallest, 22 ga, approximately the same size as corresponding gauges of copper wire. These items are readily available because farmers often purchase their own veterinary supplies and vaccinate their own animals.