sfp "computer"?

Hi Does anyone make a SFP with a system on chip "computer" that you can run a small embedded linux on? I am sure it can be done because I have a "GPON stick" which is basically a ONU with a small embedded Linux all on a SFP module. Does get fairly hot however. My application is to run some small things that I feel is missing in my switches/routers. Plug in this imaginary "SFP computer" to enhance the switch with a small Linux. The SFP slot provides both networking and power to the device. Regards, Baldur