Example of 'brilliant' apps?

[Gabriel Ambuehl]

Jonathon McKitrick schrieb:

Hey all,

We finally have a day that looks like spring here on the east coast.  I plan
to enjoy it.
I've decided that as much as I love DFly, I am not much of an OS programmer.
But are there any apps out there lately that you would call brilliant, or
outstanding?  Or that could otherwise possibly give me some inspiration?
I'm still working on my data acquisition project, but a new pet project
might be fun.
 

If you want to do the world a favor: come up with a way (cross platform 
preferably) to sync Mozilla Mail / Addressbook / Sunbird calendars with 
phones and PDA...