Clearwire and Sprint bolstered their WiMAX plans today by detailing expansion plans and new devices. The former led the news with details of a subsidized 4G notebook: the carrier plans to offer a subsidized version of the Dell Mini 10 with WiMAX that will provide the 3-6Mbps mobile broadband for less than ordering the device separately. The 10-inch netbook should cost $250 when signing up for Clearwire's 4G at the same time and will be available April 1st.