You need 250GB just for the raw captures, then space to edit them, and then to transcode the final results down to DVD etc. I am using up near on a terrabyte on just the X0 project basically.
I then have 20GB of software in current use as well, and about 400GB of video of my kid and that sort of stuff, that really can't be deleted, and gawd knows how much other stuff that *could* be deleted if only I could get my arse into gear to try and sort/catalogue/backup and remove it.
So the end result is I have a terrabyte in one PC that has almost no free space, 800GB in another that has about 60GB free, and a shelf with various hard drives on it that I need to go through, a 20GB drive in my Xbox that is now being used to temporarily store and playback the home movies... So if anyone comes to my house with a degaussing wand, I am in serious trouble...