In effect I'm working on a SaaS application where I want to give subscribers their own subdomain to access their information (in code I will be pulling the first part of the subdomain for use as their account name), similar to how Basecamp et all work. For instance, a subscriber might have the URL
acme.myapp.com. Since there could be hundreds of subscribers I can't simply add a different host header for each client.
Apache allows you to specify a wildcard (*) and will redirect acme.myapp.com to myapp.com, wherein I can perform my logic to retrieve the user's account name based on the subdomain. I'm not sure how to automatically do this with IIS (It's been a while since I've had to configure IIS for anything except a single website).
Also, is there any special provisions that I need to accomplish this? When my app is ready and I'm looking at hosting for it, will I need anything specific from the host that would limit my choices? I was also considering using Windows Azure to take advantage of the cloud - would I still be able to do this if I went with Azure as a hosting platform?