'Finger Print', and 'Firelog Xp'

Finger Print

A utility to see if any files in one or more directories have been created, deleted, or changed since the last scan. It's useful for checking if a program, e.g. viruses and trojans, has changed your all-important Windows files (this is similar to such security software as Tripwire). The use of MD5 checksums guarantee detection of file changes. FingerPrint can also be used to find duplicate files, search for files with a specific MD5 value, and save MD5 values to file (and compare with). A command line version is also included.

http://www.2brightsparks.com/freeware/freeware-hub.html

Firelog Xp

This is a simple program for people using the Internet Connection Firewall (ICF) in Windows XP. It will read the log file and show you who is trying to get into your computer, and through which ports. The data can be filtered to include/exclude protocols, connection types, and TCP flags. FireLogXP includes connections to on-line resources to give you more information on what a specific port is for and how it may be being exploited.

http://www.2brightsparks.com/freeware/freeware-hub.html