With all the “recommendation” technology companies out there fighting for business, you’d think this is a tough market to be in.

By some counts, there are at least 50 to 100 active companies in this area.

But some companies, including Strands, and apparently Baynote, say they are making revenue from their technology, though they won’t comment whether they’re profitable. Their recommendation engines offer up products, music or news articles to people based on their personal tastes.

They’re forging ahead, even as other companies, such as Kleiner Perkins-backed Aggregate Knowledge, are finding the sector a big headache, and are laying people off.

A recent Yankee Group report says the technology is promising, yielding up to a 400 percent increase in click-through rates on some sites. However, Yankee predicts a consolidation. ATG already acquired one player, CleverSet. “In the next 4 to 5 years, only three to four personalization engines will survive in each major market,” according to the report, which also says companies will fight over the mobile sector next.

For now, we’re going to limit our summary of the sector to five companies making news lately.

Strands — Surprisingly, this company says it is making $12 million a year, mostly by licensing its technology to other undisclosed companies. It makes money by taking a share of the increase in sales it enables with its customers. Some of the revenue also comes from advertising. Strands says this revenue number is honest (in other words, it’s real revenue, and doesn’t contain any commission or fees that are passed on to another party).

It has served mainly large companies so far, but here’s the challenge: Larger companies are building their own recommendation engines. So Strands is increasingly  going after medium and smaller customers. Spokesman Gabriel Strands’ Aldamiz-echevarria says significant revenue may therefore be elusive in the short-term. While he estimates there are between 50 to 100 recommendation companies now, he predicts they’ll be drastically winnowed down over the next year or two — and Strands will be a survivor.

In the meantime, Strands is trying to make money from consumer-related products. It’s best known for its music player for mobile devices that lets you discover new music, connect with people, and share your tastes with friends. It reports 40,000 weekly downloads. But it’s moving into other areas, including personal finance: Strands lets banks serve up financial product recommendations to their customers, based on a customers’ financial background and practices. Last week, it announced a deal with large Spanish bank BBVA to test Strands’ Social Recommender. BBVA has 42 million customers, engaged in 1.3 billion transactions online a year. “Each time you pay with your credit card, you’re expressing your taste,” says spokesman Aldamiz-echevarria.

Strands also wants to help users control of their taste profiles, and allow them to take that profile with them. Along these lines, Strands is working on data portability, so that its users can let Amazon recognize their tastes if they log in at that site.

Strands has taken a colossal $55 million in venture backing, including $39 million last year, the sanity of which you have to question. Strands will have to perform well to make money for its investors. On the other