This is a proof-of-concept Bluetooth receiver that can receive bluetooth (advertising) packets using an FPGA and an antenna, read: straight RF into a SERDES port sampling at 5Ghz.
(From: https://github.com/newhouseb/onebitbt)
Somehow I don’t think Xilinx ever intended for standard SERDES ports to be used for direct RF sampling, but it’s pretty incredible that it’s possible.