you can easily configure nagios to monitor a point beyond your isp connection. nagios is a great tool for a small business network to monitor performance as reachability, with a very small footprint on a server. there are distro's like echelon
http://www.echelonlinux.org/docs.html which will run on a very basic system and monitor whatyou want, with minimal configuartion by all accounts.
why did you tag this post with "please"?
