I've been doing a lot of work and a lot of experimenting recently scanning slides, negatives and prints into one large photo library. This process is now in it's later phases and I'm looking for a suitable online home for a version of the library contents. I'm looking carefully because I really badly want to make the right decision as I don't want to go through this process again, EVER!
As the largest online repository of images Flickr has to be looked at seriously and I'm currently, with next year's image acquisitions in mind, experimenting with the Flickr slideshow options and how they can be embedded in blogs, websites and whatever else you fancy.
Here's my first trial, I like the fact that you can tailor the size to fit.