It's unlikely you'll find someone willing to just give out ETH so that you use it as gas. If you just need to cover gas costs, and need a very small amount, I would reccomend that you start mining via your smart phone, there are several options out there right now that allow you to do that, and even though it's not profitable and you are unilikely to make a lot of money out of it, because the entire mining market is dominated by big players and expensive hardware, you'll still be able to earn at least a little bit in order to cover your gas costs. I'm not sure as to the exact amount you can earn, I guess that depends on what phone you use, but it will definitely be enough to cover and sort of gas costs associated with whatever it is you want to do.