I have seen a few different types of hot shoe adapters and flash triggers for the NEX range of cameras over the last few years. And I have been very happy with the simple JJC MSA-10 (ISO hot shoe adapter for nex) that I have been using, but last week i sew a dedicated trigger and receiver for only 14€ and thought I would give it a try.
My set was branded with the name WanSen but they may be distributed under several different names