From the 
Bizarre Labs website:
Collapsing a can with air pressure
Atmospheric pressure is strong enough to crumple a metal can.  This  can also be done  using an aluminum soda  (pop) can. Put a little water  in it (app. 3cm) and heat on a hot plate  until it begins to steam. If  you must do this over a gas or other flame,  don’t use a very high flame  or an empty can; the paint may burn or,  worse, the aluminum may melt.  Using tongs, quickly flip it upside down  into a small tray of ice  water, which should be 6 or so inches (15cm)  deep. The water will  prevent the outside air from entering. A little of  the ice water will  be drawn up into the can, but not enough to equalize  the pressure, and  the can will crush.
Egg in a bottle
 
  
 
  There are plenty of  things to do with eggs, one being the egg  in the  bottle trick. Use a shelled, hard-boiled egg. The egg needs to  be free  from cracks in the white and smooth. Find a bottle with a neck  just  small enough that the egg won’t fall in (a carafe, milk bottle, or  some  baby bottles–possibly an ice tea bottle). Wad up a little piece of  paper and drop it in the  bottle (you can also use 2 or 3 wooden  matches). Light the paper or  matches, allow to burn out, and  immediately put the egg in the  bottleneck, where it should be sucked in  (making a very interesting  sound in the process). Actually, the egg  isn’t sucked in, it’s pushed.  The fire heats the air, causing it to  become less dense and to rise out  of the bottle. This causes a decrease  in air pressure inside the bottle.  The higher pressure outside the  bottle pushes the egg in.
 

  A reader recently reminded me that you can easily get the egg out again   by turning the bottle upside down and blowing into it very hard. When   you take your mouth away, the egg should pop out due to the increased   air pressure in the bottle.