What is the biggest loss you have had on the stock market?

[Shortie]

When investing in anything including the stock market there will always come a time when you will have a loss, some losses are not a big deal and other losses may be a lot to chalk up and take in. Getting a loss no matter how big or small is never something anyone wants to have to go through but it is something anyone who invests will go through at some point. 

What has been the biggest loss you have had when investing in the stock market?