http://www.red2blu.com/ You send in the hd-dvd cover art and $5 and get the Blu-ray version. You actually get to keep the hd-dvd disk/box. $10 for Planet Earth and $15 for Matrix and Blade Runner box sets. It only in the U.S. though.
Thats a crazy business model. Great for consumers tho. Good find, shame it'll never hit the UK. I really wish HD-DVD had won the race just to piss on sony's bonfire.
HD-DVD was superior, it still saddens me the way it all ended. Too bad I hocked my "reds" ages ago to feed my GC dev hardware collection