I'm in the process of writing a scheduling application on a shared hosting server. So far it doesn't look like my scheduling will have to be any more granular than daily, but that could change later. Ideally, I'll want to use a Windows host so I write my application in .NET but I'm open to using a PHP+*nix host.
In a shared hosting environment (read: cheap) how can I write an application where notifications can occur on a scheduled basis?