The way to do this is to buy XP:
More and more PC distributors are offering this for free.
Buy an XP PC before a certain deadline (for example Dell have a deadline of 31/3/07).
They then send you the Vista upgrade CD for free - you just pay for delivery.
Mesh (UK) are just charging £15.00 for the delivery of the Vista upgrade.
http://www.meshcomputers.com/Default.aspx?PAGE=RUNTIME_VISTA_PRICINGBased on the fact that when you buy a PC you don't normally get an actual Windows install CD, I quite like the option of buying a XP system and get the Vista upgrade CD as it is better than buying a Vista system and not having a Vista install CD. At least this way you have an installation CD - even if it is purely to upgrade XP to Vista.