Symantec recently released a report that estimates that over 70 percent of emails received in most people's inboxes is spam. The report also discusses the recent trends toward MP3 and Google search spam, the Ron Paul spam scandal, and the continuing fall of image spam.

Also included in the report are the 10 known categories of spam:

• Product Email attacks offering or advertising general goods and services. Examples: devices, investigation services, clothing, makeup
• Adult Email attacks containing or referring to products or services intended for persons above the age of 18, often offensive or inappropriate. Examples: porn, personal ads, relationship advice
• Financial Email attacks that contain references or offers related to money, the stock market or other financial "opportunities." Examples: investments, credit reports, real estate, loans
• Scams Email attacks recognized as fraudulent, intentionally misguiding, or known to result in fraudulent activity on the part of the sender. Examples: Nigerian investment, pyramid schemes, chain letters
• Health Email attacks offering or advertising health-related products and services. Examples: pharmaceuticals, medical treatments, herbal remedies
• Fraud Email attacks that appear to be from a well-known company, but are not. Also known as "brand spoofing" or "phishing," these messages are often used to trick users into revealing personal information such as email address, financial information and passwords. Examples: account notification, credit card verification, billing updates
• Leisure Email attacks offering or advertising prizes, awards, or discounted leisure activities. Examples: vacation offers, online casinos, games
• Internet Email attacks specifically offering or advertising Internet or computer-related goods and services. Examples: web hosting, web design, spamware
• Spiritual Email attacks with information pertaining to religious or spiritual evangelization and/or services. Examples: psychics, astrology, organized religion, outreach
• Other Emails attacks not pertaining to any other category.

Symantec puts out these reports each month and if you aren't reading them, you should be. They are packed with information and statistics on spam and spammers and provide a solid foundation for your spam fighting strategies.