I haven’t tried it, but allegedly [Qemu](http://www.nongnu.org/qemu/) will convert .vhds to work with VMWare:

- http://blog.mozmonkey.com/2008/vpc-ie6-ie7-ie8-on-mac-os-x/

Anyone able to confirm/deny this?

(Qemu might or might not work on the Mac: see http://qemu-buch.de/cgi-bin/moin.cgi/FrequentlyAskedQuestions#head-5b05ca765afc90fc092967e7a03cd5644759437f)