Defender security

[Boarder1]

What is the best visual deterrent / security device recommendation you could fit to a defender (apart from a couple of Dobermans in the back)?

Just looking at preventing anything happening in the future, I know if someone really wants the car, they will take it, but would like to give them some sort of hassle factor first!

Thanks

[Boarder1]

Thanks for the replies, have also looked on defender2.net and some useful advice there as well.