What type of carrying case do you use?

I'm in the market for one just in case I need to bring my (big!) BP to the vet's office in the future.

I was at the pet store today and saw some large rodent plastic carrying cases, meant for guineas and bunnies which would probably work just fine. I also saw some large fancy canvas bag's meant for small dogs. Has a nice sturdy bottom and a zip top with mesh around the sides for air vents.

What do you guys use?

depends on the weather. On hot summer days I use one of the canvas bags with mesh. Sometimes I will put the snake in a pillowcase inside. I have also used the plastic critter cages but not often. When its cooler I use a variety of insulated carriers depending on what snake I am taking. I have a small styrofoam cooler as well as a couple of smaller cooler bag. Oh and they go in these in a pillowcase and I use something to warm the inside, either a heat pack or hot water bottle. When I do shows I have a large collapsble cooler and a few snakes will fit in it, all in pillowcases. I make sure they are all around the same size so no one crushes anyone else. If there is a smaller snake it will be in a plastic carrier.

I have one of the canvas dog carriers for my lizard (while he's still a somewhat tiny thing) and it works very well. My only real concerns with it are during cooler days, or chilly vet rooms, there's no way to "insulate" it. Granted they shouldn't be in that very long, but you never know.

For the snakes I use extra 15 qt sterilites (with duct tape on the lids, hot water bottle / heat packs, towel along the bottom, etc), but I'm not sure how that would work for larger snakes - and the next size up is rather unwieldy to lug around. I'll be looking into those styrofoam coolers, however, as that sounds a lot more handy than these tubs :P.