Salesforce.com has long had a public AppExchange software marketplace, but now it's going to give customers the ability to create their own private AppExchanges where employees can download applications to use in their jobs. Private AppExchange is generally available as of Friday to customers running Salesforce.com's Enterprise and higher editions, said Sara Varni, senior director of AppExchange marketing. However, those customers can give employees who don't use Salesforce.com itself access to the private store for $5 per user per month.