This is not a new one and has been doing the rounds in various forms for some years.

Basically the email contains a number of graphic images of a persons thumb that is supposedly suffering from a flesh eating type of infection. In it's most recent form the email claims a new breed of spider is spreading through Australia with devastating results if you are bitten.

The original email looks to have started in America and since spread to other countries with local modifications.

The email is definately a hoax and the images almost certainly photoshopped.