A new social search engine is promising to pay users for finding correct answers.

ChaCha launched in Alpha test mode yesterday, but the site has since closed to the public owing to huge demand. 

Blog site SearchEngineWatch said that ChaCha combines Wikipedia, Yahoo Answers and About.com, with the bonus of real-time results supplied by humans. 

The site offers two ways to search: traditional computer-compiled results; or live help from real people known as 'guides'. Users can interact with guides via an embedded instant messaging system.

Brad Bostic, co-founder of ChaCha, told SearchEngineWatch that the site has lined up 2,500 guides for launch, mostly students, retired people and parents at home.

Guides need to be invited by an existing recruit and must work their way up through four hierarchical levels: Apprentice, Pro, Master and Elite. Only the latter three categories get paid for answering queries.

Pros receive $5 per search hour, while Elite guides get $10. Masters also receive 10 per cent of the amount their network generates. The network comprises people introduced to the ChaCha Underground by the guide.

An advert looking for new guides appeared on classified advertising site Craig's List on Monday.

ChaCha claims to be the brainchild of a 'Mr Jones', who is also credited in the advert with inventing voicemail and "specific technology components behind iTunes and the iPod".

"We are inviting highly capable individuals to be some of the first people to see and use the revolutionary tools that are unique to ChaCha," the advert read.

"The job entails pay between $5 and $20 per hour (performance based) and the time commitment is extremely flexible. You can work whenever and wherever you choose, for as much time as you want, part-time or full time."