From Easytravelreport.com:
This week a general strike is planned. 48 hours. 19 and 20 October Wednesday and Thursday. Greek air traffic controllers will strike Wednesday 19 and Thursday 20 October 2011 from hour of 00.01 Wednesday until 24.00 Thursday local.
Also joining: Greek seamen, all ferries will strike. From 6am Monday 17 October to 6am Wednesday 19 October. Will take a while to get ferries back to normal.
Telecommunications will be joining in on 19 Oct.
18 -19 Oct bank employees on strike. Bring cash ATM will be empty. You may find museums and archaeological sites closed.
Proastiakos suburban railway to strike from Tuesday-Thursday.