Some insurance companies will honour your NCB on a second car and when I had an Admiral Multi-Car Policy then as long as the cars were registered in my own name, then I'm pretty sure they carried over my NCB... if they didn't then the prices were crazy low for some reason?!
...I'm sure we won't have to wait long to hear the immortal "Call Paul @ Need to Insure" chat roll out shortly though.
Cheers,
Grant