Brick is the informal term for a device used by IBM CEs in the 1990s. It physically the size of a house brick, hence the name. It had a small LCD display and a full keyboard on its face. It was used to communicate service call information to the CE. It can be seen as a predecessor to the Blackberry.
"In 1983, IBM developed a private packet radio data network called DCS (Data
Communication System) for the use of its field engineers. This was used for call dispatch and call reporting and some other data applications. The terminal device consisted of a hand held data terminal about the size and shape of a house brick, by which name it was consequently known. The radio infrastructure was provided by Motorola and operated at 4.8 Kbps on a carrier frequency of 800 MHz. The network covered the major cities of the United States but the FCC licence did not allow the service to be sold to other users. At the same time, Motorola was building a network using the same technology for public access. In 1990, the IBM and Motorola networks were joined to form a public access network known as ARDIS (Advanced Radio Data Information System). The original implementation of ARDIS used a protocol known as MDC4800, but a new protocol called RD-LAP is being introduced alongside with the advantage ofoperating at 19.2 Kbps."