Voicethread

Here is the link to Voicethread. It's a site where you upload a picture and students comment on it by typing a response or recording a spoken answer. I like that students can ear and see each other's responses. Lots of possibilities in multiple subjects. I paid a $10 educator fee that gives me a closed system with my students and only they and others I invite to my groups can post on my pictures. You can also do it for free.

Oh, and you can embed it to a website, a mashup, etc...pretty cool...
Annnd, you can always type text (i.e. a prompt) into the picture box and have them respond.