There's something that's been bothering me slightly about the taxi drivers - sometimes I'll flag them down and ask them if they will take me somewhere.This will be a typical scenario -

Me: Can you take me to (insert area here)
Taxi Driver: [nods...and drives away]

I ignored it the first few times and took it as a national joke against me (it wouldn't be the first country to perpetrate such a move), but after a while it became somewhat concerning. Later I was having a converstaion with my friend who was telling me a story of what happened when he went to a shop in Damascus

Friend: Have you got any cereal
Shop Keeper: [nods - remains silent]
Friend: Where is it?
Shop Keeper: [nods...]
Friend: Have you got any cereal?
Shop Keeper: (angrily) NOOOOO

and so my friend realised that in Syria, the nod of the head in a straight and strictly upwards movement means "no"

It's those little things that you can't get from Arabic lessons at home.
Especially when you oversleep and miss them anyway.