I own this Canon IXUS 50 camera for more than two years now. It's a fine device, but it has some small lacking features where I often asked myself if this could be enhanced with a new firmware.
Until recently, when I read about the
CHDK project: It's a kind of firmware enhancements for Canon cameras. It doesn't fully replace the real firmware, but adds additional stuff (I must say I don't fully understand what they do). And now they have
an experimental port for the SD400, which is built into my cam.
The first big killerfeature one will notice is that the cam now has a battery monitor, which is the most obvious lacking feature of the original firmware.
One more thing I always would've liked for my cam is a better video compression. The video quality is quite good, but the cam just can do mjpeg, which leads to big files and limits your maximum video size to about 20 minutes. It seems CHDK has some better compression video mode, but I'll have to dig deeper into it. Beside, I can now record raw images. So there's lot's of cool stuff to play with.