[FahnRobier]

a HN "zen garden" type of redesign would be a fun challenge, limiting yourself to modifying the css only.

http://www.csszengarden.com/

[geuis]

Sadly, the underlying table structure and layout of the site isn't condusive to this. I spent a few days earlier this year trying to write an iPhone interface for HN by just modifying existing styles and it didn't work out so well.