Eric Migralia, of Yahoo! YUI fame, has just released a tool, Inbound Link Analyser, for listing and analysing inbound links to any site. It's utilises YUI extensively and, I'm sure, provides a fantastic example of how to use a number of the core YUI components. I strongly recommend a browse around the source. Data for the tool is taken from Yahoo!'s Site Explorer API and del.icio.us.
So far the tool has helped me unearth plenty of inbound links I hadn't discovered through the usual suspects (Google Analytics, Feedburner etc) so given how much I like trawling through this stuff I'm guessing I've got plenty of fun filled browsing ahead of me.
The interface also lists other pages that have been indexed for the domain entered. Clicking on these or any of the inbound links opens separate tabs within the interface for you to analyse those resources further.
Eric's written a short introduction over on his blog (also newly released) so I'd suggest heading over there and checking that out first.
Here's a link to an analysis of my CSS Sprite Generation tool. It provides plenty of data to start exploring the tool with.

This tool looks like it could be very useful. Will have to have a look at in depth. Thanks
I think I still need to learn the ropes on this tool. I find it is pretty definite for me to use the metrics quirk.biz for backlinks, seo elite and other yahoo tools - it seems like a good tool but have you found this to be pretty accurate?