If you’re looking for the ultimate way to wake up your roomie, or just want to give someone a good old-fashioned heart attack, the Sonic Grenade might just fill the bill.
To startle your unsuspecting victim, simple pull the pin and lob your grenade in their general direction. The Sonic Grenade lets out an ear-shattering sound that should scare (and annoy) the bejesus out of just about anyone who’s not legally deaf. As an added bonus, your unknowing victim cannot shut off the grenade without the pin. It’s just $13.95 from Firebox.com.