Easy way to do ajax uploading with paperclip in rails?
You can try remotipart
(http://os.alfajango.com/remotipart). It's a gem fine integrated with Rails 3.1 and 3.0.
I have tried it, and all the ajax-file-upload handled like magic.
EDIT:
You'll find two versions of ajax upload on https://github.com/apneadiving/Pic-upload---Crop-in-Ajax.
Branch master
: it uses http://aquantum-demo.appspot.com/file-upload
Branch uploadify
: It uses Uploadify: http://www.uploadify.com/
Both have built-in Crop.