While playing Halo Reach on xbox 360, a player sent me a PM saying they were recruiting for a group called SPECWARCOM.
I replied and they sent me an invitation to an invite only game. After some time changing my armour and colour schemes they sent another PM with a cell phone number and asked me to text that number in half an hour.
The player who sent the initial recruitment message was named "SEAL A Murphy" and the player who requested a text message from me and who sent me their cell number was named "ODST T Parker". I fear this was an attempt to gain personal details from me, ie my cell phone number and an attempt to steal my identity.