Thinglink is a tool for creating interactive images by embedding icons with links to text, video, sounds or other images. If you want to create an image from scratch using painting tools, Odosketch is an attractively designed online tool to rival some of the simpler desktop programs. Paper by FiftyThree for the iPad is an alternative - beautifully designed and a winner of this year's Apple Design Award. Draw Island is more child-friendly and mixes the conventions of painting and drawing programs by including lines and shapes alongside a free-hand pencil tool. Colour selection is rather non-intuitive, but the animation option is promising.
Mapwing is a virtual tour creator that locates images and comments on a map of a building or site - the map can be created using a basic drawing interface or by importing an image. Creating a tour is a straightforward step-by-step process and there is a gallery of tours to explore. Overall, the site does its job well, though the finished tours are a bit dull - this one being a prime example!
Finally, if you are looking for good quality images that can be freely used in blogs, on websites and/or in documents, then try Photopin or Pixabay - two really well designed and useful sites.
Now for a couple of Top 10s - each in no particular order.