Implementing the save_to_file option is easy to do but you will still need to run the script manually (or use a crontab entry) to get an updated listings file. I'll make sure it's added on version 1.1.
From this I got a great idea!: Have latest threads auto-update to a file only when a new posts/reply's are submitted. I have a theory on how this can be done.
Making Latest_threads auto-update only when new content is posted is a little harder to do but would be the ultimate solution. I was looking more at the UBB code and I think I may know exactly how I can accomplish this. This would take care of any I/O & CPU overload in resources for any site small or big.
Adding auto-update will be the first thing I do after I release v1.1.
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