You can get a kit for this Lucasnerd-approved cable organizer from GeekCook, or you can fix one up yourself using sections of that Princess Leia cardboard cut-out you owned in the '70s.
You did, don't deny it.
~Not-"Not-So-Handy Andy" Jack
The only issue with this "lock" is that it's less of a security mechanism and more of a test of strength between you and the person coming in. If a 300-pound linebacker gives the door just one good yank, he'll probably send you flying from the toilet seat with who-knows-what strewn all over the floor.