This will find anything that was accessed in the past 30 minutes:
sudo find / -amin 30
Finds anything larger than 10k that was modified today:
find / -size +10k -mtime 0
Finds any file larger than 1MB that was not modified in the past year:
find / -type f -size +1M -mtime +365
Finds any php file larger than 1k that was accessed in the past 30 minutes:
find / -size +1k -name "*.php" -amin -30
