My hosting suspended my account today. My account have used a huge amount of CPU and memory in the last few weeks. My account was brought back so we can monitor it for the next few days and try to find out what exactly is doing this.

The symptom:

"lets give it 24 hours and i'll monitor the server for the next few hours. This usually hits around 11:30 MDT. the process was a php process. it was repeated like 20 or 25 times. and those 25 ran for 4 hours until at the last when it shot everything up"
NitroZone.Net

This sound like a cron job was running some serious PHP script, the server have a script execution time limit of 15 minutes, so this could only happen by either setting the script execution time to 0 or repeatedly run some PHP script by using command line or HTTP request.

I haven't locate the script problem yet, but I start closing down some of the not often used plugins.

Wait for the answers tomorrow :)

BTW I think people can construct scripts like this to take down a server :)