Totem visualisation plug-ins ?

[Vincent Trouilliez]

Totem comes with a few visualisation plug-ins to give you something to
look at when playing  audio-only files. But none find my fancy. 
Is it possible to install new plug-ins for this purpose, where to get
them ? And can they be customized by hand by tweaking some obscure
configuration file somewhere ?

I had a look at Totem's website, but didn't find any info about this
particular point...

--
Vince