As a cultural crossroads between social networking and Wall Street, you just can’t beat a bank robbery.

That was the case last year, as a woman twittered away during a New York City bank hold-up. As the Silicon Alley Insider describes it, the woman — who dubbed herself Traveling Anna — was tweeting while standing in line at her bank. Just after typing the requisite 140 words or less on an upcoming social event, she followed up with this: "my bank was just held up - with me in it. HSBC 34 and 8. also my whole trackball is GONE!!! im locked in the bank still."

You know it’s a technology-obsessed culture when someone experiencing a bank robbery is preoccupied about the loss of her trackball.
But those are the cards society has dealt itself and far be it for banks and social networking companies not to take full advantage.

Thus the increasingly aggressive move by banks to woo customers over Twitter. The social networking behemoth brings a great deal to the table for banks. First and foremost are the 75 million Twitter users, as measured by RJ Metrics. While around 80% of all Twitter users are described as infrequent users, there are still enough tweeters to attract the attention of the biggest banks in the U.S. Twitter itself pegs its “active user” base at 18 million and estimates that number to rise to 26 million by the end of 2010.

The number of actual banks that have Twitter accounts is up in the air. estimates that 15 banks and 22 credit unions had active Twitter feeds but that was back in March 2009. (For a list of banks and their Twitter URLS, click here).

Of the big banks that do offer Twitter to customers, services are sketchy — it’s as if banks are just getting used to the idea of reaching out to customers using social networking tools, but haven’t really figured it out yet. For instance, Wells Fargo (Stock Quote: WFC) dedicates a half-dozen customer service staffers to Twitter exchanges with customers. And Bank of America (Stock Quote: BAC) has appointed a “Twitter rep” to handle user questions.

E*Trade (Stock Quote: ETFC) taps its money-savvy “spokesbaby” to connect with users, earning points for ingenuity and for pumping the brand, but again, not much actual advice for bank customers. But so far, most of the exchanges, at least from the bank’s point of view, are of the "Hi, I’m from (fill in the name). How can I help?" variety.

Banks really have nothing to lose by trying to leverage Twitter. They can reach legions of younger customers who may not have settled on a bank yet without the heavy expense of a big advertising campaign.

But the technology is limited — mostly, bank customer service representatives just point users to the appropriate 1-800 number or URL to address a problem. And right now, consumers aren’t biting — or at least taking a big bite. Most financial institutions count their Twitter followers in the low four-figures.

That said, banks and social networking, as a marketing tool at least, are just getting started. Hopefully it won’t take another bank robbery to get the word out, but bank twittering is apparently here for the long haul.

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