Possible Clues:

• 'r u kidding?!'
• Mild online oath
• 'I'm shocked!,' in a text
• Texting interjection
• 'WTF, I cnot BELIEVE this!!'
• Texting gasp
• Texter's "Zounds!"
• Texter's ''Holy cow!''
• Small-screen gasp
• IM gasp