The Jargon File (version 4.4.7, 29 Dec 2003):

wheel of reincarnation


    [coined in a paper by T.H. Myer and I.E. Sutherland On the Design of
    Display Processors, Comm. ACM, Vol. 11, no. 6, June 1968)] Term used to
    refer to a well-known effect whereby function in a computing system family
    is migrated out to special-purpose peripheral hardware for speed, then the
    peripheral evolves toward more computing power as it does its job, then
    somebody notices that it is inefficient to support two asymmetrical
    processors in the architecture and folds the function back into the main
    CPU, at which point the cycle begins again.

    Several iterations of this cycle have been observed in graphics-processor
    design, and at least one or two in communications and floating-point
    processors. Also known as the Wheel of Life, the Wheel of Samsara, and
    other variations of the basic Hindu/Buddhist theological idea. See also 
    blitter.