> You have at least to put all these 100 URLs (which change 
> often) also into the filters.
> And what to do for the different extensions?> ...
> +*www.geocities.com/blabla/*.extension1
> +*www.geocities.com/blabla/*.extension2

This is not possible - you can not mix host/extension in 
one single filter. But I may add support one day for regexp 
(regular expression syntax), like +www.
(foo|example|bar).com/*.(gif|jpg) (maybe in a future 
release - but not for the current one, which is now in 
freezing process)