Decrementing an ordered list

I have a ordered list in an html document, you know, like

<ol>
     <li> item one
     <li> item two
</ol>

which displays, obviously, as

1. item one
2. item two

I want to make these numbers countdown rather than up. Anyway to do this using html/css without manually numbering everything?

You can reverse CSS3 "counters"

see this answer I posted recently, it might help

How can I center the text but not the number label of an HTML ordered list

note though that that won't work in IE7 however if you hardcode the "values" in reverse you'll get the fall back too, obviously hardcoding the values should work for every browser on it's own too.. so the CSS3 counters is maybe a wishlist item ;)