Microsoft has long been rumoured to follow Apple and Google into the hardware market, and also to expand its Zune into a fully featured phone.
Could happen on Monday, as the firm has been sending cryptic press event invitations out to US scribes. A source told CNET that this event will unveil the codenamed Pure and Turtle slider phones, which will run on Verizon Wireless' network and go on sale within the month of the event.
However, these devices won't be based on the acclaimed Windows Phone 7 OS first presented at MWC in Feb. That will be later in the year.
More likely, they'll emerge from the almost-forgotten Danger subsid that Microsoft bought two years ago. Danger achieved brief success with the Sidekick, a kind of BlackBerry precursor for younger users.