Getting scripts to run unattended
Ovine can be run from a command line (and gives nice feedback messages when you do), but really needs to be fired -off at regular intervals (every hour or two will do) by another application to work usefully. I use the Windows Task Scheduler to run it. (Thanks to Martin von Loewis for his advice on how to get this working). Mac and Linux (etc.) users will have their own ways to do this.

What worked for me
In Task Scheduler, create a new task, and select the "host" application (I currently use the Python.exe), and then add the path to the script as an argument directly after the application path in the "Run" field (with just a space between them). If the path to the script contains any spaces, surround the path with double quotes.

Setting the schedule
The Windows98 Task Scheduler has a rather unclear interface, in my opinion. After some trial and error, I found that the following settings seem to work fine. Set the task to run daily, and in the advanced settings, set the repeat value to 1 hour and the duration to 23hrs 1min.

The repeat value you choose depends on how bothered you are about using CPU cycles to crunch random numbers in the Bovine client. A 1hr repeat value gives an average 30mins "random time" per buffer file completed. If your machine crunches a buffer in 5 days, this gives about 99.6% of available time actively crunching your assigned buffers, which is good enough for me.

Important note
When you set up a scheduled task (in Windows 2000, possibly on other systems), if you assign a password to the task, ensure that this is an admin password. Reason? If you change your personal password at the system level for any reason your scheduled tasks will not be able to run, as they will still have your old password. How much warning do you get when this happens? Er, none at all. Nice.