If it's a single shared connection, I think a Linksys VPN router on each end should be sufficient for your needs. But I've got to be upfront with you; I haven't worked with a VPN for this kind of setup, so there could be issues I'm not aware of. VPNs are more commonly used for network access rather than desktop sharing; I'm not sure if it's really going to buy you anything, since remote access packages typically include encryption inside the application; it's not lke you can turn it off when you have VPN encryption available.