Adding variables to blockthemes

Firstly, let me say that blocktheme is an awesome little module.

Today though, I ran into an interesting case. I wanted to add a RSS feed icon into title of my "recent comments" block. Simple enough, took a matter of minutes to achieve. But then I thought, wouldn't it be really cool if I could say on the block page, use this blocktheme, and then specify a RSS feed to use with the theme, so that the theme becomes reusable rather than having the RSS feeds location hard-coded.

This becomes an even bigger thing when you look at theme developers who might like to include a bunch of blockthemes with their theme to cover cases like this: minor variations on a theme that would be desirable on a fairly regular basis.