Is there a way of creating a unity account that just plays a recording and doesn't allow callers to leave messages?
On a Standard Subscriber mailbox you can just tweak the After Greeting Setting to say Goodbye or Hang up. I would go with Goodbye :) By doing this the Mailbox will no longer accept messages.
Indicate the action that Cisco Unity performs after the greeting plays:
Take Message - Cisco Unity records a message from the caller. Click the Take Message link to view the Messages page.
**Say Good-Bye - Cisco Unity plays a brief good-bye, and the call is disconnected. Click the Say Good-Bye link to view the Good-Bye call handler.
Send Caller To - Cisco Unity sends the call to the destination that you select:
Call Handler - Sends the call to the call handler that you select.
Directory Handler - Sends the call to directory assistance.
Greetings Administrator - Sends the call to a conversation for changing call handler greetings over the phone.
**Hang Up - Disconnects the call. Use carefully; unexpected hang-ups can appear rude to callers.
Interview Handler - Sends the call to the interview handler that you select.
Sign-In - Sends the call to the subscriber logon conversation.
Subscriber - Sends the call to the subscriber that you select.
Hope this helps!