VNC is the way to go as a replacement for RDC. RealVNC for the PC, Chicken of the VNC for the Mac. Just know, if you'r connecting over the WAN, things are a bit choppy (unless you have a lot of bandwidth). I use something different though. KDX is a cross-platform client/server setup. Very light on the CPU, and very easy to use. It also give me access to file transfer, chat, and multi-user support (with approp. permissions) without having to create accounts/ACL's on the computer. KDX suffers from the same slowness when running full screen desktop, but I like the other features enough to prefer it over VNC.