Well, you could use MAMP, or even install Ubuntu on a spare box. I run an older B&W G3 for Ubuntu and leave my development to my G4 (yes outdated dual 800MHz but it gets the job done for me). I used to use the Ubuntu* machine as a "staging" server but with the access to high speed internet over the past 9 years it's not a bother to just set up a subdomain or directory with a host, in our case Dreamhost. So the need for a development platform is negated by the fact that you can develop on Dreamhost itself. If your looking for no FTP access I'd suggest SSH Tunneling, an easy way to accomplish this GUI wise is to use MacFuse and MacFusion to set up the server to act as a networked drive.
As an Apple developer of over a decade, your golden on this platform, we can now be known as more than just Print people!
*When it was staging it was running Yellowdog
MacFusion Usage and Install Instructions - http://www.sccs.swarthmore.edu/users/08/mgorbach/MacFusionWeb/