The design and use of CPUs on a single inexpensive circuit are discussed, Necessary additional equipment is noted, and the potential for using the microcomputer in the laboratory is explored, Computer circuits have been decreasing in size and cost since computers were first invented. The ultimate reduction is now reality: a "computer" on a single integrated circuit, less than 1/8 in. square, for a price well under $100 in quantities. Capability continues to grow, with more powerful designs and faster technologies promising greater performance and lower prices. Foster (1972) has extrapolated the current trends to predict a computer on a chip, having processing power equivalent to a 7090, for about $1 by 1997. Even current large-scale integration (LSI) devices tend to reach the $10-$15 range once quantity production is achieved.Thus, it would seem that we now have an embarrassment of riches in computing power available at a very low cost. If a computer is available for under $100, then a wide variety of applications in psychology, education, and everyday life should be immediately achievable. The computer in a briefcase described at this conference last year (Norman, 1973) should be a reality soon, if not right now.This paper explores what else is needed to make use of this abundant technology and some possible courses of action. A range of microprocessors is considered, with one explicit example; the additions that are necessary are explored; and some suggestions of the applications strategies that could be followed are given.