NCIDpop is a Macintosh and Windows client for NCID (Network Caller ID). The Macintosh version is Universal (32-bit Intel/PowerPC) for Mac OS X 10.4 and later. The windows version is also 32 bit.
See the release notes and screen shots at http://ncid.sourceforge.net/ncidpop/ncidpop.html for fixes and enhancements.
See http://ncid.sourceforge.net for information on NCID.