That is a popular request but is not currently supported.
Are you distributing your form as an HTML/web form or a PDF? If you are using PDF you cuold add the Email action to the submit button, let me know if you'd like more information on setting this up.
I would prefer to use it online (html/web form) and to receive forms that were filled in, as a pdf file.
Another option would indeed be to use the form as a 'dynamic' pdf. If I understand correctly, AdobeForms offers the possibility to create a 'send by e-mail' button underneath a dynamic pdf then?
I would be interested in more info on that.
FormsCentral PDFs are not dynamic. What is your reference to Dynamic? Are you thinking of forms created by Adobe LiveCycle (Dynamic XFA forms)? FormsCentral creates "static" AcroForm type forms.
You can use a PDF designed in and generated from FormsCentral in a more traditional work flow where you add a Submit button with the submit method of your choice to the PDF and don't use FormsCentral to collect the responses.
One other options is to save your FormsCentral form as a Submission enabled PDF and then edit that PDF in Acrobat adding an additional Submit method to the existing Submit button that would open the default email client and attach the PDF to an email, it would also submit the data to FormsCentral, so if the user did complete sending the email you would recieve the PDF back as well as have the response data in your FormsCentral account.
This FAQ describes how to edit a FormsCentral PDF in Acrobat: http://forums.adobe.com/docs/DOC-3661
There are several tutorials online for adding the Emailo Submit method to a button, take care not to modify the existing actions on that button so you do not break the FormsCentral submit if you are trying to have both: http://www.youtube.com/watch?v=Jql1wp5Gofs