I've been using the white thin-frame Apple Keyboard, the one included with the white iMacs. It may not be an AEK-II, but it's certainly not a bad keyboard either, it's currently tied with the ThinkPad keyboard (which you can get as a usb keyboard for desktops) as my favorite.

I have considered getting an iMate and an AEK-II for my iMac, but if it's no longer really possible to use them (with Leopard), I may not do that. I've also considered grabbing a ps/2 adapter and finding a Model M.