One of the things about piping tail -f is that it goes into buffered mode and needs to be specifically disabled (which on is available on specific tools). Here’s a little one-liner to look at our referers coming in that was good fun:

tail -f access.log | grep -v --line-
buffered '"-"' | grep -v --line-buffered 'upcoming\.org' | awk -W interactive '{
print $11}'