caker wrote:
Time for someone to code this up as a cron-job (be nice, only poll every few hours or something) and set it up to email you...
Here ya go. This is quick and nasty and will mail you every time you run the script. Just disable it in cron once you've been alerted

It requires "lynx" to be installed to do the request
Code:
#!/bin/bash
# Your linode user name
USER=YOURUSERNAME
# Where to report mail
EMAIL=YOUREMAILADDRESS
# What level to send emails at
WARN=90
URL="http://www.linode.com/members/bw/?user=$USER"
data=$(lynx --dump $URL)
max=${data#*<max_avail>} ; max=${max%%<*}
total=${data#*<total_bytes>}; total=${total%%<*}
let pct=100*total/max
if [ $pct -gt $WARN ]
then
echo -e "Over $WARN% of quota used\nBytes transferred=$total (allowance=$max)\nThis is approx $pct%" | /bin/mail -s "Linode bandwidth warning" $EMAIL
fi