Lidl - Ultimate Speed Jump Starter
I bought this from Lidl for £34.99 which seemed very good value, it can start Petrol cars upto 2.0L and Diesel upto 1.6L. Mine is a 1.9L Diesel so I doubt this will be capable of starting it, but I will be putting that to the test in the near future.
http://www.electronicstuff.info