This site claims (update: incorrectly, see below) to provide instructions for cooking an egg by placing it between two live mobile phones:
# Switch on phone A and place it on the table such that the antenna (the pokey thing at the top) is about half an inch from the egg (you may need to experiment to get the relative heights correct – paperbacks are good if you have any – if not you may be able to get some wood off cuts from your local hardware shop).
# Switch on phone B and ring phone A then place phone B on the table in a similar but complementary position to Phone A.
# Answer phone A – you should be able to do this without removing it from the table. If not, don’t panic, just return the phone to where you originally placed on the table.
# Phone A will now be talking to Phone B whilst Phone B will be talking to Phone A.
# Cooking time: This very much depends on the power output of your mobile phone. For instance, a pair of mobiles each with 2 Watts of transmitter output will take three minutes to boil a large free range egg. Check your user manual and remember that cooking time will be proportional to the inverse square of the output power for a given distance from egg to phone.
(via Negatendo)
Update: Esther sez, “Cell phones communicate with the cell tower, not each other. The
egg shouldn’t be between the phones, it should be between the phone(s) and
the tower for this to even have a snowballs chance in hell of working.
Furthermore, a cell phone only spits out 2W of power for *very* short
intervals. As a matter of fact, cell phones try really hard to minimize
their output power to A) conserve battery life and B) play nice with the
other phones on the network. You don’t want a phone close to the tower
blasting all the other phone signals into oblivion.”
Update 2: As many have pointed out, Esther’s explanation misses the fact that cell-phone antennas aren’t directional.