Just put the first iteration of our mobile-friendly website together yesterday! There are still some issues with it but at least it works right on any mobile device that identifies itself as a "handheld" device to the .css file. (Well, it should anyway. At least the horizontal scrolling is has been minimized.)
There are still a few things to address (the forms are sometimes way too wide, for example) but, for the most part, it's good to go. (I think. I've only tested it on an iPhone simulator-like thing and on my Treo.)
I think it might be time to throw money at an iPhone. Or maybe an Android...