[on topic] What's your favorite less-popular open source app?

[Shane Hathaway]

Everyone talks about the major players in open source.  I'd like a 
discussion about some of the good, smaller programs that aren't well 
known.  I'll start off with some of my favorites.

- XCA: A simple GUI for creating and managing SSL certificates.  Easy to 
use for those of us who want to mess with SSL certificates without 
deciphering how to use openssl directly.

- FileLight: The best way I've seen to visualize what is eating up disk 
space.

- Twinkle: Like Ekiga but more focused on being a phone rather than a 
videophone, making it easier to use IMHO.

Shane