The Pipe Magic Tools (PMT) are a small collection of filters which
can be added to UNIX pipes. The filters include:

speed
    Measures the speed of the data flowing through the pipe

throttle
    Controls the speed of the data flowing through the pipe

rot13
    The famous rot13 algorithm

rot47
    The not-so-famous rot47 algorithm

tolower
    Converts all alphabetic characters to lower case

toupper
    Converts all alphabetic characters to upper case

WWW:    http://hansmi.ch/software/pipe-magic-tools