Is there an IDE out there that does structural syntax highlighting?
I'm the author of Codekana. Indeed, what you describe above was the main goal for the product. BTW, I'm about to publish an article about the "making of" and the underlying technology, which is pretty nifty. It will probably be available next week (March 26, '09 or so). Recommended reading, if I may say so myself.
The reason Codekana only provides outlines, instead of a colored background, are limitations in VS's text rendering extensibility. I will hopefully be able to implement a solid-background version at some point in the future, although it will definitely require serious hacking and "rocket surgery".
I would have commented above, instead of providing another answer, but my reputation doesn't allow commenting. :(
[UPDATE: Thanks for the upvotes, now I can comment!]
The closest thing that I've seen is Codekana, although doesn't have "background syntax-highlighting" it colorizes the different flow-control structures:
(source: codekana.com)
(source: codekana.com)
- Red for loops
- Green for if-blocks
- Brown for else-blocks
- Aquamarine for switch-blocks
- Olive for exception blocks
- Orange for 'return'
Coderush does structural highlighting:
(source: devexpress.com)
It quite feasible you could write your own plugin with DevExpress that achieves your exact original screen shot.