Not sure exactly what these things are called.... They look sharp and unpleasant but are actually quite nice and soft (yes, curiousity got the better of me).
triky76, analogabaires, fruchtzwerg_hh, jetnz81, jezzyjung, kathepalacio, tsingtao, bkspicture, bravebird, imbaaa, nina1707, tobiasdelfa, trw, troch, weleasewoger72, hervinsyah, lawypop, lucas__amorim, blueglitter, fergiesilva & nuhdos.
I'm glad I'm not the only one who would do something like that! ;-)