I have a big problem with getting students to practise orally outside of the classroom and lesson. For my large group of French BTS (HND equivalent), oral expression is essential for their final exam.
Building confidence and spontaneity is an important part, playing with the language and involving communicative situations rather than formal grammar work.
I make a point of speaking to them as much as possible outside the lesson, in the car park, canteen or greeting them at reception in the morning which helps a lot.
For one-way practice and assessment outside of class we recently set up an account on Skype just for voicemail use. The students can practise their oral work that I give them in class and when they feel ready they can leave it as a message on Skype at anytime. I listen and correct it later and send them back a text message.