On one David Blaine TV special, he approached a homeless man and gave him fresh coffee, but in a touching twist, David Blaine seemed to conjure up coins through the coffee. The coins seemed to lift out of the coffee right in his hands. Personally I love this trick and think its a great magic trick to perform almost anywhere
Preparation for this street magic trick

Get a coffee cup like that out of a coffee machine with the "personal solitaire" graphics on the side. Remove the bottom of the cup with an X-acto knife and place it back, and fill the cup three quarters full with coins.

The key is to pack the cup tightly with the coins. This will "seal" the cup so that it doesn't leak. Then pour in the coffee with enough to cover it completely. You may want to put some creamer in your coffee to darken it a bit.
How this street magic trick was performed

Present the coffee to someone. Grip the cup from the bottom and push u on the bottom, and shake the cup. As the coins "unsettle" the coffee will spill between the cracks and the coins will appear!

so how did the coffee disappeared?