I'm soldering one of the last batches of RFid readers for work, before we skip to a "professionally produced" version. To be honest, I'm a bit relieved that we are replacing the arduino + MC522 modules with something created by guys that actually know stuff about RFid. But on the other hand I can be a bit proud that these readers are working for 2 seasons now and with pretty decent results, knowing that they worked close to water (sometimes even in the water...) and in the sunlight and rain. In a way we are a hardware start up as well, even if we actually don't want to. I will soon release the design files etc. and tell some stories around it - actually looking forward to that.