Signal & Switch is a co-operative game for 2-4 players from David Thompson and KOSMOS in which you collectively manage a rail network that must pick up goods in four cities and deliver them to one or two port cities, depending on which side of the game board you use. Everything about the design is straightforward to understand and play, but you are nicely challenged to handle lots of uncertainty — thanks to the cards and dice — and complexity, thanks to the system of signals and switches that you need to monitor and adjust as trains move between cities.
I'd write more, but I must away and