RPC over HTTP is a great way of connecting directly to your exchange server mailbox over the internet. This is in fact the only way I check my email as we have our production servers on an isolated network with a dedicated leased line. So I am never on the corporate network.
I have also been rolling this out for customers with SBS 2003 and Exchange 2003 and it works really well. Below is a collection of articles with regards to deployment and bandwidth requirements.
I’ll be blogging more about this.
Planning Exchange Architecture in a Bandwidth-Sensitive Environment
Del.icio.us : httpoverrpc, rpc