Is this a guessing game?
There are at least 7 different programs that use the .clp extension.
and wouldn't you know it, my crystal ball is out for an upgrade today.
.clp - PCPaint, Pictor bitmap clip art
.clp - Microsoft Windows clipboard file
.clp - wxCLIPS file
.clp - DeskMate clip
.clp - Corel Quattro Pro clip art file
.clp - CA-Clipper compiler script file
.clp - GoDot image format