There's physlock[0] as well, as vlock (apparently) has some limitations according to physlock(1):

       physlock  is  an alternative to vlock, it is equivalent to `vlock -an'.
       It is written because vlock blocks some linux  kernel  mechanisms  like
       hibernate  and suspend and can therefore only be used with some limita‐
       tions.

I can't attest to this as I've only used vlock, so correct me if I'm wrong.

[0] http://github.com/muennich/physlock