Need bootable cloning software

Anyone know any reliable cloning software that I can also create a bootable USB drive with? That is to say I need to clone one HDD to another and was wondering if there's any cloning software that I can actually also boot from.
I will be cloning my laptop's HDD to an external HDD before sending it in for repair (in case the repair center wipes it) and I don't feel like mucking about with partitions AND doing a Windows installation on an external drive just for this one time.

Anyway, thanks for the help guys.