FINDSTR /G: is quite useful, for example, if you have a master file containing all employee details, and say an RFID scanner at the entrance to a restricted workplace which generates a file containing just the RFID number from their tags, you can identify the employees that have accessed that area using eg.:
Code:
FINDSTR /G:"dailyfile.txt" "masterfile.txt" > who_was_here_today.txt
_________________________
Peter.

"I spent 90% of my money on women, drink and fast cars. The rest I wasted." - George Best