Website monitoring service?

Does anyone use a good website monitoring service that they're happy to recommend?

I use uptimerobot.com a lot. It's free.

use google analytics alerts with specific thresholds set. they will email you if bounce > X , traffic falls by Y etc.
hth
niall

Using Google Analytics is my preferred choice as well, let me know if you want me to point you to a tutorial baldidiot!

Thanks guys!

I'm more after a remote uptime monitor (been having problems with a VPS I have) that checks every 5-10 minutes, such as the one squigley mentioned. I wasn't expecting free - thats awesome! :)

I would recommend Unica.

It's quite advanced however you can make it simple.