Here's something I'd like to get others' thoughts on. Let's say you want to do something with your design that you know is not going to be accessible by everyone. For the purpose of this discussion, let's forget about designing for the blind, other languages, wireless devices, etc. Let's also forget about highly-specialized sites that are selling the technology itself. For example, 360 panoramic photography used to require Java in order to play. If you were designing a site (in those olden days that required Java) that sold 360 panoramic photography services, obviously you'd have no choice but to require Java to view your samples. Let's just think about our average Joe computer user. Those who might visit your real estate site that uses 360 photos. The feature doesn't have to be Java. It could be anything: A high-resolution design, ActiveX, a browser plug-in, Ajax, whatever... What the specific feature is, does not matter. But let's say it's a pretty key item that appears on every page. We all know that we can't always accommodate everybody, but what is your cut-off point for deciding whom to accommodate? Do you design for 100% compatibility? 90%? 50%? Some other number?