Can you use your own promo code, or one generated by someone at the same address as you?
It is theoretically possible, but DreamHost will certainly take a dim view of it is they catch you, because it would constitute a breach of their policy.
As Simon has already said, this is against Dreamhost policy.
but I wonder why you would bother trying to use your own promo code, when there are many others available that offer the max discount.
Pay just [color=#CC0000]$22.40[/color] for 1 year Dreamhost hosting, use promo-code [color=#CC0000]MOJO97[/color]
Save [color=#CC0000]$97[/color] on all 1 and 2 year plans!! (Max saving on monthly plans too!!)