When I am testing, I always keep an eye on the logs because they are a valuable resource for finding problems on the system. They can act as an early warning system. The tail commnand alongside with view or vim are great ways to explore big log entries.
Some simple examples:
>> tail -f web_app.log import.log >> tail -f *.log
>> tail -f web_app.log import.log | grep ERROR
... or get and read log from remote host
>> ssh remoteUser@remoteHost "tail -f /var/log/app/app.log" | tee local.log
less is more
More convenient way to monitor logs is by using less. less + F app.log allows you to switch between watch mode and navigation mode with ctrl+c and back to watching mode with F. Very helpul when you need to search, find occurrences, create marks etc.