I built myself a carrying case, based on the tutorial I found here: http://www.gloden.info/quadrocopter/Koffer/ (Thanks for that great idea!).
Basically, it's just a cheap aluminium case from a DIY shop, and some cut-to-shape styrofoam - but it does an excellent job, easily as good as the expensive cases you can buy.
As an added twist, I added a holder for my Nexus 7 (filled with a piece of cardboard in this picture). Basically, I just scraped away to rubber foam that covers the inside of the lid in a few places, and glued some velcro straps in... now I can put the Nexus 7 in there and fasten it with the velcro, no rattling around or sliding out of pockets.