HINK of the T-Mobile Sidekick as the Ginsu knife of the mobile wireless class. About the size of a deck of cards, it not only makes phone calls but also sends e-mail and instant messages, browses the Web and takes pictures.

Now Sidekick owners who cannot resist using all those functions have found a way to gather the tribe: through a sort of communal Weblog, or blog, called Hiptop Nation.