When our baby was very little, he slept in the carrycot of his pram.
Since the outgrew that, we have used the Phil and Teds Traveller:http://www.productreview.com.au/p/phil-ted...aveller-t2.html
It's a bugger to put up the first time or two, but not as big a deal as the reviews make out. It's super light and very compact. It is hard to fit back in the carry bag, but we stuff it in the box it came in and that still fits in our suitcase so no need to check in separately. Weighs 2.7kg!!!!
We have definitely been glad we had it on one camping trip where there were mosquitoes and big bugs inside our cabin, but not in DS's zip-up cot. It is great for squishy hotel rooms and caravans as not as big as usual portacot.
You're supposed to zip the mattress into the bottom of the cot, but we just lay it inside. It's so thin I can't see how it would be a hazard and we use normal cot sheets on it.
We were once charged $70 for portacot hire for one week, and wish we had bought this a week earlier!