A UI that looks good and has some nice effects is something that makes it more pleasurable to use a phone. (Yes, I count my N900 as a phone)

Look at the Sense UI that HTC has developed for their latest Android phones. I think it is actually very nice to use and IMO it makes the experience of using Android better.

Having used the 3rd party rom with Sense UI integrated on my brothers Nexus One (that I flashed for him) and then coming back to my N900, I felt like my phone was just missing that extra ingredient that makes it fun to use.

If you know of any alternative user interfaces that are in the works for N900 post the info here.

If you are working on a UI post here.

Let us know your thoughts and ideas about what would make the UI of N900 better and how we can achieve it.