Genuitec has updated their Pulse
tool, which is designed to provide easy and free access to multiple configurations of Eclipse. The update includes access to hundreds of plugins (yes, hundreds) and also offers a low-cost way to provide your custom plugin configurations to others.
Pulse is, as mentioned, free; commercial offerings such as MyEclipse and Instantiations' SWT Designer are part of the catalog, and Pulse can help manage your subscriptions to those as well.
Pulse also can manage Callisto and Ganymede configurations of Eclipse.
Pulse is actually quite useful; I don't actually start up Eclipse without it any more.