Had a brief trip to Koh Samui last year on the way to Koh Tao. We had a two hour wait for the ferry so rather that sweating it out on in the waiting shelter my wife and I popped over the road to a Thai eatery that seemed to be built exclusively from building materials found on the side of the road. The food was simply amazing, like the Som Tam above which was only 120 baht and the steamed crab was fantastic. Beats the hell out of the broken bits of raw crab they sometimes use, which can make you horribly ill. Combined with a couple of bottles of Singha the time went very quickly. If you want to find it it's directly accross from the 7-11 at the ferry pier near the big buddha.