300% ED on a magic weapon. Not sure about the +min/+max -- I think it's +30 min, +63 max.
About the BotD sword -- I've no reason to believe it hacked or duped. A friend of mine does this (ironically I taught him how). You set your character to 'read-only' and put the runes in. If it's a low-end variable mod, you save and exit and put the runes in again, till you get a high-end variable mod, at which point you turn off 'read-only' and save and exit. I did this at the start of 1.09, and that's how I know -- haven't used ever since. I don't think this is cheating that badly. Why? Because some of the other SPF members use it. I remember numerous threads where people (I won't mention names, can't remember most anyway) said they had re-rolled their HotO/BotD/other high-end runeword to get perfect or near-perfect stats.
Not to sound like I'm defending of flaming anyone, but it's just my 2c.