I have a 104key Filco, and it's heavy, like, really heavy, at least compared to rubber dome keyboards, if you want to consider carrying it from time to time, image carrying a 18" laptop with big batteries on it or something like that (talking about weigh). Just on a personal note, I carry my keyboard and mouse, twice a day to my job and back to my house, since I have only one of them (filco majestouch2 104key with red switches and a Razer Naga), if I'm able to afford new ones for job on the future, I would still be doubt full about leaving those in the office, with all those noob developers around, I don't want them near my stuff so, I rather take them back with me. LOL.
Still, you can carry a full layout keyboard on a backpack with the proper height, just try to measure it. Also, if you get one like the DAS, or BWU, forget about carrying it anywhere, those are bigger and get scratches easy, not worth carrying them around.