launching screensaver manually

[Adam Hardy <adam.ant@cyberspaceroad.com>]

I want to launch my screensaver manually sometimes, so I think it would 
be best to have an icon on my desktop or menu but I can't get the cmd 
line right.

/usr/lib/xscreensaver/xrayswarm -root

doesn't work.

/usr/lib/xscreensaver/xrayswarm

does work but launches a new window containing the screensaver graphics 
- so obviously I need to do something different with the -root option. 
The man page says the -root option should launch the screensaver in the 
'root' window and I assume that's what I need.

Thanks
Adam