Related Clues:

• Type of post-caffeine state
• Percipient
• Hushed 'Hey, you!'
• ''Hey, over here''
• ''Heads up!'' e.g.
• Sound the alarm
• Far from drowsy
• ''Ahem!''
• ''Check this out!''
• Whispered ''Hey!''
• Secretive ''Hey, buddy!''
• Library attention getter
• Furtive attention-getter
• Alternative to 'Hey!'
• Soft "Over here!"