I'm not sure why I'm entertaining such thoughts lately. Maybe it's all the time I'm spending dickering in Rails/Django/ASP.NET MVC/CakePHP.
I'm used to Template Toolkit. I see there's a Template-Python in the works. I keep fantasizing about having Template-Ruby, Template-PHP and Template.NET so I could simply use my entire sites template directory across code bases. More often than not, my templates are just blocks, loop, iterators and simple ifs. No real magic.
Some days I wish I knew enough about parsers/lexers to start something. Then I look into them and remember that it makes my brain melt.
Somedays, the lack of having a true CS degree is a drag.
This is something that I was thinking about three years ago.
I never did anything about it though