The 3367 trick:

This trick is similar to the 7-11-13 trick.

 

It's harder to do, but it looks far more miraculous!

 

Get a friend to pick any 2 digit number e.g. 74

 

x 3367

 

To work out the final answer you have to imagine the original number written out three times e.g. 

747474 then divide it by three. 249158

 

This one takes practice, but unlike the others, it's very hard to see how it's done!