You know how family sized meals come with multiple cups of fountain soda and if you are packing it to go, it always spills on the journey home. I think I have found the solution in these huge tumblers from Fairprice/Unity Pharmacy. It also works on individual cups if you need to chuck it into your bag instead of holding it in your hand.
The sizes go up to 1.4L, 1.8L and even 2L and it costs $10 or $12 a bottle. It can hold temperatures 0 to 90 degrees celsius, nothing too intense like boiling water. This tumbler has a wide opening for ease of pouring.
Another tip I have is to get perfectly popped corn from the cinema concessionaire, it's always better than homemade. I bring along oversized ziplock bags to prevent it from spilling on the way home. A quick price comparison, $13.20 @ cinema concessionaire for two 730ml sodas and one 3L popcorn against $4 for 3 x 93.3gm bags of microwave popcorn and $2.50 for 1L of soda, the equivalent value by weight is $46.50 @ any supermarket.