If I do a low level format on a hard drive (write zeroes), there's no way at all to recover the files, correct?

Hya Rory.

If you use one of these:

http://dban.sourceforge.net/
http://www.killdisk.com/

Then I doubt that it will be possible to recover any data at all, but if it is then it will cost ALOT of money to recover anything.

i used to do some decomm work for the dept. of defence here in australia..
the only way you can wipe the data so it's completely unreadable...

is to drill a hole through the disc

but those 2 programs, or about 5 low level formats...will make it so ridiculously hard to get data back

Ok, cool, thanks. I just wanted to make sure because I might be selling my computer (hard drive included) and I didn't want someone being able to recover my family photos and things like that.