ChipPlay

ChipPlay was a Chip's Challenge program by Willie McClure, released around 2001 or 2002. It was used for playing custom level sets with one executable file and one INI score file. Due to lack of interest at the time, Willie removed it from the Internet not long after its release, and today it is still unavailable online.

ChipPlay seems to have been ahead of its time, because its method of playing custom CC levels is now one of the most popular methods, and it inspired the similar programs Chip's Controls and Chip's Challenge Level Manager, which are both used by many.