At some point, I was flying a low cost airlines with just 1 ordinary backpack. But I didn't pay for baggage, and the bag indeed exceeded the size requirements: it was well packed. I had to hastily pay extra for the baggage, leave it behind, and then wait for it upon landing. I hate waiting for baggage claim on arrival, and there's also a possibility that it will be lost ...and at that point it costs the same as a normal flight. On the next trip, there was only one flight that suited me and it was a low cost one (and with the added baggage... well, it stops being low cost). So I've read the tariff rules, and it stated the following: I can take a 40x30x20 bag, and a laptop bag or a camera bag. So I've packed my trusty North Face Borealis (just for reference), But! I've packed my camera bag inside and in it I also loaded anything that shouldn't go to checked baggage: A charger, USB cable, power adapter, toiletries, a pair of socks, a T-shirt, a camera... Basically anything I could fit in there. To be honest with you, I only really use this bag for this purpose only. I apply this trick even if I don't take the camera with me, which is rare, but in this case I can stuff this bag even more. First of all, the bag serves an organizational purpose. Second, I can still take the bag out and send my backpack anywhere and don't lose anything critical. Third, I can take it out before check-in desk, wear it on my shoulder. And that isn't against the rules: I have a backpack that now fits into 40x30x20 box and a camera bag, which is allowed. There's one downside: it's inconvenient. Taking it out before checking, carrying it, and putting it in after. But it's fine. It's only for a very short time, and the whole process doesn't take too long, so it's not a big deal. In general, I dislike traveling with a suitcase, and limit myself to just one regular sized backpack, and I'm a greedy bastard. I'll take 5 minutes of humiliation for the benefits.