Iain asked me about other multiplayer games that work with two (other than Caylus, that is). Well, here’s a small list:
First of all there are few games with modular boards that scale really well. Samurai is the king of scalable games, as it works really well with two, three or four. Some might actually prefer it with two, since that removes some issues with seating order.
Attika is another one. With different amount of players it’s a different game, and I happen to like the two-player game a lot. Antiquity is a similar case, and here two-player game helps to cut the game length, too.
Some games don’t have modular boards, but adjust the size of play area. Two Knizia titles come to mind: Einfach Genial and Through the Desert. Both work with the full range of players and are quite good with just two. I think I prefer Einfach Genial with two, actually.
Finally games with no modularity or adjusting play area: Africa is fun with two, especially with two experienced players it’s really a big filler that plays really fast. There’s a bit of setup time, but it’s worth it. I tend to play it with Tommy every now and then if it’s just two of us, though I think Genial is taking over this niche.