a) A pack of dominoes. There were seven dominoes in the pack. FAIL.
b) The world's tiniest sellotape dispenser. The size alone renders it almost useless - if you're even able to get tape off the bloody thing with your human-sized hands, you'll find you have just enough tape to do fuck all with. Helpfully, the tape itself had been put on the dispenser the wrong way around, promoting it to full pointlessness.