I use a dog tent, like the one in this link:
http://www.ebay.com/itm/OxGord-45-Pet-Dog-Cat-Playpen-Tent-Portable-Exercise-Fence-Kennel-Cage-Crate-/400690881963?var=&hash=item5d4b09a5ab:m:myD45fzR4Ry7vSiCXME_k7Q
The only issue with that is that it doesn't have a poop tray, instead I put a liner (I had one made for it, that is washable), and take it out in the morning. I hang toys and pouches from the top and the sides (which are all mesh). Before I was using one of those cages that you can fold, but it wasn't very big, specially now that I have 4 gliders. This is very big and easy to carry around.
I've also hear good things about the weekender (sold by The Pampered Glider: http://www.thepamperedglider.com/travel-accessories) and the likes.