Proglet

[UK]

n. A short extempore program written to meet an immediate, transient need. Often written in BASIC, rarely more than a dozen lines long, and contains no subroutines. The largest amount of code that can be written off the top of one's head, that does not need any editing, and that runs correctly the first time (this amount varies significantly according to the language one is using).

Compare toy program, noddy, one-liner wars.