The VinGarde cases are expensive but worth it.  Fantastic padding for your bottles, straps to hold everything in place internally, two big straps around the outside and a durable zipper.  The case rolls very well when full of wine.  It appears to be robustly constructed for durability, unlike some of the other wine carriers I have seen.

Can be used to transport up to 12 bottles but you can also take out some of the bottle padding and use the case to haul lesser quantities of wine along with your other clothing / travel gear.  It's not like you need to haul 12 bottles on a long weekend trip.