Hello
I've created yesterday a Python script to conform 30p to another value (making a longer movie if you go for 24 fps).
It takes a Quicktime file and changes a few bytes of the file to alter the default 30 fps value to whatever you want. It's fairly basic but I can now easily drag & drop my .mov files on it and instantaneously get a 24p version of the videos (again, just by conforming)
This is absolutely platform-independent (PC users need to install Python, I'm using v2.5)
The drawback is that it won't stretch audio for you.
If some of you are interested, I'll post the script there.
Thanks to linus for providing me a sample file

Cheers
JS