Researchers at UC Berkley and UC San Diego set out to determine if spam is profitable by launching a spam business of their own. They infiltrated the "Storm network" which uses hijacked home PCs to distribute spam and were able to send 350,000,000 emails promoting an online pharmacy offering herbal libido enhancements. Deliverability was poor at under 25%, but that still allowed 82.7 million messages to reach computers. 10,522 clicks drove 28 purchases of $100 each, for a daily income of $140 for the campaign. The researchers only tapped 1.5% of the Storm network for their test. By extrapolating to the entire network they estimated a full-time spam operation could generate $3.5 million per year.