I. P. Sharp Associates, IPSA for short, was a major Canadian computer time sharing, consulting and services firm of the 1970s and 80s. IPSA is particularly well known for its work on the APL programming language, an early packet switching computer network known as IPSANET, and a powerful mainframe-based email system known as 666 BOX. It was purchased in 1987 by Reuters, which used them until 2005 as a data warehousing center for business data.