FOR the past three years Daniel Brandt has been running his own search engine. He called it, cheekily enough, Scroogle.

Scroogle.org is the antiGoogle. It carries no advertisements and survives on donations from its users, usually less than $20 (£9.90) apiece when and if they make them. It doesn’t even have its own technology and relies instead on “scraping” search results from Google’s site and offering them up, minus the ads. Traffic has doubled every year and now Scroogle has passed 100,000 visitors a day.

Brandt said growth was down to one word: privacy. Unlike its well-funded rivals, Scroogle keeps no record of who is using its site or what they are looking for. Within an hour of using the site, the search terms are gone for good.

The internet has become a depository for our most private thoughts and information. Details we would be reluctant to share with a doctor are routinely volunteered to Google, Yahoo and other search engines, and can easily be traced back to the computer it came from.

“A lot of people don’t realise search engines save everything you search for,” said Brandt, a longtime Google critic. “The more these issues get into the press, the more people realise that when they sit down at their keyboard, they’re being watched,” he said. But after a series of scandals, that laissez-faire attitude seems to be coming to an end.

All the big search groups have been tightening up privacy policies. Last week the search engine Ask.com went furthest by offering a new service, Ask Eraser, that will wipe out a searcher’s queries within hours.

Search information is valuable, allowing firms neatly to target ads to a person’s interests to generate billions in advertising revenue. Search logs also improve the engine’s performance, companies argue. Google uses search-log data to run its spellchecker – the system that asks: “Did you mean: Arnold Schwarzenegger?” when you type in his name spelt wrongly. Search data are also used to detect and fight spam and other attempts at internet fraud.

Google, the industry leader, stores personal information for 18 months, as does Microsoft’s search engine. Yahoo and Time Warner’s AOL retain search requests for 13 months. But they are not the only people after the information. Search records have increasingly been targeted by the police. Last month in North Carolina a court denied Robert Petrick a retrial after he was convicted of murdering his wife. Google was one of the strongest witnesses against him. His wife, cellist Janine Sutphen, went missing in 2003. When police became suspicious they raided Petrick’s home and found the computer consultant had Googled the words “neck”, “snap”, “break” and “hold” before his wife was killed. The prosecution argued Petrick had also viewed a document entitled 22 Ways to Kill a Man With Your Bare Hands and researched body decomposition and the topography of the lake where his wife’s body was later found.

Few people would complain about internet searches being used to catch criminals, but divorce lawyers regularly subpoena search-engine firms looking for dirt on warring spouses. Highly personal information can be used in a variety of ways that were never sanctioned by the person who entered the search terms. Then there are the risks of accidental breaches. Last year AOL inadvertently released detailed queries conducted by more than 650,000 Americans. Searches released by AOL included “depression and medical leave”, “fear that spouse is contemplating cheating” and “how to kill oneself by natural gas”. Searchers were quickly able to identify some of those behind the queries. While AOL is the only firm to have suffered a major leak so far, critics say that more are bound to come, and internet users should be wary of how firms can legitimately use their personal information.

The London-based watchdog Privacy International ranked Google as “hostile to privacy” in its survey of internet firms, its lowest rating. Rivals Yahoo and Microsoft also fared poorly.

In recent months, Ask.com has been trying to seize the high ground on search by casting itself as the alternative to Google’s “monopoly” and by emphasising privacy. A spokesman said: “Some people are willing to lessen their concerns about privacy to get more services, but, for a certain set of people, privacy reigns supreme.”

It is difficult to erase digital footprints, however, and the information typed by users of Ask Eraser will not disappear completely. Ask.com relies on Google to deliver many of the ads that appear next to its search results, so Ask.com will continue to pass some query information to Google.

“One less place for data to be breached is a good thing,” said the Ask.com spokesman. Others are less impressed. Danny Sullivan, editor-in-chief of Search Engine Land, a blog that covers search engines and marketing, said more privacy moves were likely but that increasing privacy on the web was no simple matter.

“All the major search engines have moved to toughen up their stance on privacy this year. I think it’s useful, but the changes they are making gloss over the more detailed logging that goes on when people use these services,” he said.

Google will anonymise data after 18 months, so that any searches done, say, 19 months earlier, would not be traceable back to a person’s computer. But when people log on to one of Google’s services, Gmail, for example, and use the web history feature, which records and saves searches, Google is keeping track of all the websites they visit and all their searches “and they are going to keep that for ever”, Sullivan said. Data are linked far more closely to you personally and you don’t have any control over it.

What happens next may well depend on investigations under way into Google’s privacy policies. In Europe and the US it is under pressure from politicians over its purchase of online ad firm Double Click, the largest digital-ad server with a huge data-base of consumer searches. Between them, Double Click and Google know an awful lot about how people behave on the web.

In the meantime, for those concerned about their privacy, there’s always Scroogle. “Until we get too popular,” said Brandt. “Then I’m expecting Google will pull our plug.”

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