At the moment, I only have a Xbox Gamertag: FocusSight64. (Unless you want to count 3DS and WiiU, which my WiiU Name is FocusSight, due to character limits, and my 3DS Friend Code is 3609-1244-4024) In any website or service I join, I usually try to keep the same name everywhere, and not once has this exact username been taken before on any service I've joined (besides WiiU and 3DS, due to character limits).