Luckily one of my neighbours was awake and shouted at them out of the window. They ran off.
That was the final straw for me, so I bought one of these......
http://www.ebuyer.com/279867-xenta-fi89 ... ra-fi8905w
This is a screenshot of the camera view. Sadly I can't zoom out or move the camera remotely (cheap camera) but it alerts me when there's activity and it's also a visual deterrent.

I bought some stickers from eBay to put on my car windows as an added deterrent.
http://www.ebay.co.uk/itm/5-x-SMALL-CCT ... 801wt_1163
There are some limitations to this setup. I have to keep my PC on all the time for it to record all the activity.
I'm thinking I may eventually buy a cheap PC purely dedicated to watching my car.
