mitochondrial/nuclear targeting sequences?

I’ve been searching for information regarding the specific targeting of proteins to the nucleus and/or mitochondria. Does anyone out there know if such sequences have been documented? I know the human/mouse sequences are fairly well known.

The only reference off the top of the pile that looked promising is: Eur J Cell Biol, 2003, 82(10) pp.495-504

Thanks!

The Fire Vectors use the NLS from SV40 T-antigen to target fusion proteins to the nucleus, and a Mitochondrial import signal (MtLS) from Chicken Aspartate aminotransferase to target fusion proteins to mitochondria. If your goal is to target some particular protein, I think these have a good track record.
If your question is more about endogenous targeting signals in C. elegans, I’ve never really looked into it.