A road trip is nothing without regional produce, and with farmer stalls set up along the road, as you drive to Bangkok from the south, you can stop and buy/try each regions speciality.
This region is famous for salted duck eggs. The duck eggs have a bigger yolk than hens eggs, and are ideal for salting. This regions eggs are less salty than I make them, and they don't keep as long, so be sure to use them up within the sell by date.
I hard boiled the eggs shortly after buying them, and kept them ready in the fridge to be made into yum-eggs for rice porridge and as a side dish. Like that they'll last a month or two without problem.
At this stall they also sold century eggs and salted dried fish, but the main thing here is definitely the salty eggs. If you miss one stall, don't worry, there are plenty, as you drive along, you'll see another stall a bit further down the road.
You can find groups of stalls all along the side of the road, I bought mine at the map location below.
View Appon's Thai Travel in a larger map