Slide is a place that users can upload pics, or get them from online sources, add effects to those pics and then create a sldieshow to share with others.
Sliderocket
SlideRocket is designed to help you make great presentations that engage your audience. There is a free version but you must sign up.
Roxio Photo Show
PhotoShow allows the user to add pictures and videos, generate slide shows automatically but allows customization, and then you can share with friends and family.
Windows Live Photo Gallery
Import photos, organize them into albums, and edit them. Use photo tools to create panoramas, movies, slide shows, and more.
Kizoa
Create personalized slideshows, then add music and text, choose special effects, and then burn to a dvd, post on a website or share by email. You can also edit and add effects to pictures before creating.
Slideshare
Here you can upload PowerPoints, PDFs, and more and share them with the world. You can also find pre-made slideshares with wide-ranging topics.
Showbeyond
Showbeyond allows you to easily grab your images, then you can add your sound and text to create multimedia stories that you can share with the world.
Smilebox
Smilebox allows you to quickly and easily create slideshows, invitations, greetings, collages, scrapbooks and photo albums right on your computer.
Photo Peach
Quickly create slideshows from uploaded photos and share the shows via internet or embed slideshows into your webiste or blog.