Forget non-farm payrolls. If you want the lowdown on how the economy is doing, look for trends in spam, the unsolicited emails offering “Pon0s enlargements,” “low-cost mortgage solutions” and “ReplicaRolxxez”.

The wacky prose of these oh-so-special offers gives some sign of consumers’ hopes and fears. Spammers get quick responses to their mass missives, so they follow the zeitgeist closely. For example, soon after the US Federal Reserve Board sliced the overnight interest rate at the end of January, spammers reacted by boosting the number of email spams offering mortgage refinancing solutions and pre-approved mortgage loans. The proportion of spam dedicated to mortgages jumped to an all-time high of 10%, according to Commtouch Software Ltd, an anti-spam provider.

But it seems even the most gullible stock market gamblers are thinking twice to judge by the drop—from 19% to just 2%—in the share of spam dedicated to so-called pump-and-dump stock tips during 2007, according to Internet security services supplier MessageLabs Ltd. Promoters tout thinly traded penny stocks that they own, in order to drive up prices just long enough for them to dump their shares.

Other promises of quick riches—lottery scams and fake luxury goods—are gaining ground. But the big winning category is sexual enhancers. In the second half of 2007, the lure of uninhibited pleasure enlarged its share from around 50% to 70%.

Three years ago, Bill Gates, chairperson of Microsoft Corp., predicted the death of spam by 2006. But it accounted for more than 90% of all emails globally in 2007. The rich vein of market information is worth something. So the next time a helpful-sounding stranger offers you 37% gains, either in some obscure biotech company or something else altogether more private, you might just pause for—sociological—thought.