If you get an email supposedly from a Mark J. Burnett at www.valuehost.com, referring to a chargeback on your credit card, it's a scam. The email comes with a .zip attachment containing an executable. If you're silly enough to run that, presumably Bad Things will happen.

Valuehost, a UK web host, confirm this as a scam (see http://www.valuehost.co.uk/noc/).

Steve