If your plan is to watch it, then why oh why aren't you just converting it to a smaller file? The n900's display alone will only give you so much quality, you don't benefit from having such a large source file in any way, again, as you are limited by the device.

If you are simply storing it for transfer, splitting it, or wrapping it up in a zip or rar are you best options. Yeah, you cant access it on the phone when in a zipped format, but if your just transferring/storing, then theres no need to.

All this talk of reformatting the hard drive seems ridiculous. it almost seems that some just shoot straight for the most complicated solution, totally unnecessarily.