London: Be careful who you fall for this Valentine's Day - they may just splash your most intimate secrets across the Internet.

Thousands of people around the world have started personal Internet journals or "blogs" which expose the sort of details of their sex lives that would make Bridget Jones blush.

While explicit diaries are nothing new, technology allows stories of sex with strangers, workmates or old flames to be shared with the rest of the world in seconds.

"I don't think talking about sex is anything new - only the medium has changed," said Abby Lee, one of Britain's best known sex bloggers. "The Internet offers an easily accessible way to read and write about sex," Lee added.

Blogs - short for Web Logs - are personal websites where people publish their diaries or thoughts, talk about current affairs or link to other stories or pictures on the Internet.

Blog tracking website Technorati lists nearly seven million sex-related blogs. Their rise has sparked a legal, ethical and moral debate that pits free speech against the right to privacy of those who, perhaps unwittingly, feature in these blogs.

American blogger Jessica Cutler faced legal action in the United States after being exposed as the author of a blog detailing her steamy liaisons with six men while working as a junior aide to a senator.

Cutler, who wrote as the 'Washingtonienne', was sued for invasion of privacy by one of the men she wrote about. After being sacked, she wrote a book about her exploits on Capitol Hill and posed for Playboy magazine.

"It is amazing to me that people have any interest in such a low-level sex scandal," she told the Washington Post in an interview. "It's like: 'There's a slutty girl on the Hill?' There's millions of them."