The peer-less writers over at Cracked looked into the business of professional funeral mourners:

• Funerals are sad. Funerals where nobody shows up are even sadder. So family and friends may hire mourners.
• Being able to cry on demand is key. Preparing by watching movies like Titanic and Schindler’s List before the event can help.
• Some women in the business have been known to track their menstrual cycle to determine how difficult it will be to cry.
• Professional mourners have to come up with convincing back-stories to explain why they’re so distraught over an individual’s passing, but have never been seen before by most of the deceased’s acquaintances.
• The actors need to have a working understanding of how people from different religions and cultures commemorate their dead.