Extract the zip files to a folder of your choice and open the add-in (.xll) and workbook (.xls). Building these requires the xll library.

Download Description
xllrandom.zip [website] Random number engines and distributions from the C++ <random> library.
xllregex.zip [website] Regular expressions from the C++ <regex> library.
xllutility.zip [website] Random OPERs, timers, and Baby Huey to bang on your spreadsheet.