I m just back from LIDL and bought a paid of in Ear (open back) Silvercrest SKSK 4 A1 headphones there. They are at 4.99€ and decided to give a try and see what you can get for this price.
Well, I have to say I am REALLY positively surprised by them. They sound much better than my pair of RHA MA750I (that I paid 15x more) !
http://www.lidl.ie/en/Offers.htm?action ... l&id=53651