Crazy Message Trick Practical Jokes Calculator Two-in-one 12 digits electronic calculator: regular calculator and prank calculator. Crazy mode: Surprise family and friends with funny replies, including I H8 MATH, ASK NICELY, TRY LATER, WHO CARES, GO AWAY, and more! Normal mode: use as regular calculator (with only a push of a button). Automatic shut-off after 90 sec of inactivity. Dual power operation: solar power and back-up battery for low-light situations.