The fastest way to improve your interface is to improve your copy-writing.
The canonical online example is Moo.com with its adorably anthropomorphised Little Moo robot personality. An oft-cited offline paragon is Innocent Smoothies with their cheeky little packaging easter egg delighters.
My favourite meatspace exemplar is right here in Brighton. The Earth and Stars pub has an outside chalkboard with a distinct personality. Over the past two years, I’ve been chronicling its announcements on Flickr.
Stop looking at me like I’m a waste of space! I’m not just a chalkboard you know! I’m also a supporting wall. I provide shelter from wild beasts and tropical storms. Go inside so I don’t have to see you!
And my favourite:
Walking past the chalkboard this week, I was pleased to see that it had been updated. Taking out my camera, I read the latest message:
I’m being cyberstalked by a paranoid existentialist chalkboard.
Made me smile.