It's always an awkward moment when you forget the name of someone you met before - especially when they remember yours. Here are some options to help with the memory loss.
  1. Wear a disguise and come back into the room and introduce yourself as someone new. Once they introduce themselves go back, ditch the disguise, and return as yourself
  2. Rattle off the most common names you know in your conversation with them to see if they react to any. If they don't, make up a story about a friend with that name and try the next one.
  3. Refer to yourself in the third person throughout the conversation. They may get confused and start doing the same, revealing their name.
  4. Pretend that you've never met them before but you do have a twin, then pretend to be that new person for the rest of your life, effectively killing off the old you.
  5. Tell them you think they have the same wallet as you. When they show you the wallet tell "Gotcha Wallet!" and run around like you're playing a game, peeking for a credit card of ID with their name on it.
  6. Dump two vials of GHB into their drink. When they pass out, grab their phone and place their fingerprint over the home button to unlock it. Ask Siri "who's phone is this?" You'll get full contact information.
  7. Start dating the person until you eventually get engaged and married. On the wedding day, sneak out and grab a wedding program. The persons name is bound to be on there with yours.