That's good advice. And I've looked at going straight to the USB version of the RFID reader. My big motivation for using the Netduino though is that I'd like to add more then one sensor and even some other inputs (switches, knobs, etc) and have it do all the physical device handling. That way, I only plug one device into the system and get an array of data out of it.
In this case you could try to turn your netduino into a proper HID USB device. I haven't tried it yet myself but there is a sample in the .NET MF SDK that shows how to make a virtual mouse.
Here is also excellent article written by Michel Verhagen on GuruCE that shows how to communicate with .NET application using WinUSB driver: http://guruce.com/bl...cation-over-usb Looks like bit more work but it might be worth to give it a try.
In both cases you will probably loose ability to debug on the device via USB so you will need serial cable anyway. I surly can't wait until netduino guys figure out how to make this easier.