Regarding USB my level is at almost zero.

I would like to make an RFiD reader and send the card serial number to a PC through USB port. Preferably not as RS232 too USB, so that the user on the PC side will not have to install anything.

I have a barcode reader that is connected to a USB port. No drivers installed. When a barcode is read, if there is a program open (say word, excel, Notepad whatever) the code is displayed just as if one was hitting the keyboard.

Very neat and simple. Can this be done with a PIC?