Route HTTP-traffic outside VPN-connection

A client of mine has a server; Windows Server 2008 R2 in their main office, but most of them work from other locations. Some work from customer sites, and some work from their homes. The client computers connect to the server through a VPN connection to access corporate rescourses. But the problem is that the internet connection on their main office is actually slower than their home network, because of limitations from their Internet Service Provider; as they actually cannot deliver a faster internet connection on their main office location. The consequense of this is frustrations from their mobile users resulting in them disconnecting from VPN and working locally, and saving documents on their harddrive which means they will be lost when (not if:-)) their harddrive crashes. So I was thinking... is there any way to route normal HTTP and HTTPS traffic (and also maybe other ports like 21 for FTP) outside the VPN-connection, so they can still have a good internet experience? If this is possible we could "force" them to use VPN using the Directaccess feature in Server 2008 R2 and Windows 7 Enterprise.

For your information we are using standard Microsoft PPTP VPN, and all computers are running Windows 7 Enterprise.