The top words that spammers try to camouflage in their e-mails harp on the familiar themes of drugs, sex, and money, if not rock 'n' roll, said U.K.-based security vendor Sophos Tuesday.

"Spammers have a dilemma," said Graham Cluley, senior technology consultant for Sophos, in a statement. "They want to sell certain products or include certain phrases in their e-mails, but they also know that people have filters looking for those words. That's why they use obfuscation to try and disguise the words from anti-spam software."

Topping Sophos' list was "cialis," with "orgasms," "viagra," and "shipping" rounding out the top four.

Of the top 20, eight relate to drugs, four to sex, and only one to a non-drug product (rolex, at #14).

The highest-ranking software product or company name is "adobe," coming in at #21. Microsoft lags behind, with "windows xp" at #40 and "office xp" at #43.

Sophos found that up to 80 percent of spam uses some obfuscation tricks to try to slip by anti-spam software. The tricks, said Cluley, can range from the simple -- deliberately misspelling a word -- to sophisticated techniques that rely on HTML.