Basically, i have a list of 30,000 URLs.
The script goes through the URLs and downloads them (with a 3 second delay in between).
And then it stores the HTML in a database.
And it loops and loops...
Why does it randomly get "Killed."? I didn't touch anything.
Edit: this happens on 3 of my linux machines. 
The machines are on a Rackspace cloud with 256 MB memory.  Nothing else is running.
Are you using some sort of queue manager or process manager of some sort ?
I got apparently random killed messages when the batch queue manager I was using was sending SIGUSR2 when the time was up. 
Otherwise I strongly favor the out of memory option.
Why does my python script randomly get killed?