It was announced today that Google is taking the wraps off an Internet encyclopedia designed to give people a chance to show off - and profit from - their expertise on any topic. The service, dubbed "knol" in reference to a unit of knowledge, had been limited to an invitation-only audience of contributors and readers for the past seven months. Now anyone with a Google login will be able to submit an article and, if they choose, have ads displayed through Google's marketing system. The contributing author and Google will share any revenue generated from the ads, which are supposed to be related to the topic covered in the knol. Obviously, we can expect that the advertising option could encourage people to write more entries about commercial subjects than the more academic topics covered in traditional encyclopedias.