There is RapidCP:http://www.rapidcp.org/http://demo.rapidcp.org/
Download RapidCP V3 Betahttp://sourceforge.net/projects/rapidcp/
Seems that RapidCP may only be for *nix flavored servers.
Used to go under the name of ZPanel till there was a rift.
ZPanel may be for Windows flavored Apache servers.
Now ZPanel may well have overtaken RapidCP and their web site seems to be more user friendly - less spam in their forum:http://www.zpanel.co.uk/
I have trialled ZPanel some time ago (v2) and found it to be quite useful for it's intended purpose and far cheaper than it's big brother cPanel - you may only need v3 for your needs.
Google for 'rapidcp' and 'zpanel' for more info and links.