I've just come across and interesting piece of software. Called "Live Professor" it's basically a VST rack for live performance including very flexible routing, snapshots of workspaces that can be loaded live, cues and midi control. LS VSTi seems to run well in it. I'd be interested to see what others thought about it. It's still in beta but seems very mature and stable to me.
You can get it at http://ifoundasound.com